diff --git a/dom/camera/CameraPreferences.cpp b/dom/camera/CameraPreferences.cpp
new file mode 100644
index 00000000000..82a6ff98be0
--- /dev/null
+++ b/dom/camera/CameraPreferences.cpp
@@ -0,0 +1,243 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "CameraPreferences.h"
+#include "CameraCommon.h"
+#include "mozilla/Monitor.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/Preferences.h"
+
+using namespace mozilla;
+
+/* statics */
+static StaticAutoPtr<Monitor> sPrefMonitor;
+
+StaticAutoPtr<nsCString> CameraPreferences::sPrefTestEnabled;
+StaticAutoPtr<nsCString> CameraPreferences::sPrefHardwareTest;
+StaticAutoPtr<nsCString> CameraPreferences::sPrefGonkParameters;
+
+nsresult CameraPreferences::sPrefCameraControlMethodErrorOverride = NS_OK;
+nsresult CameraPreferences::sPrefCameraControlAsyncErrorOverride = NS_OK;
+
+/* static */
+nsresult
+CameraPreferences::UpdatePref(const char* aPref, nsresult& aVal)
+{
+  uint32_t val;
+  nsresult rv = Preferences::GetUint(aPref, &val);
+  if (NS_SUCCEEDED(rv)) {
+    aVal = static_cast<nsresult>(val);
+  }
+  return rv;
+}
+
+/* static */
+nsresult
+CameraPreferences::UpdatePref(const char* aPref, nsACString& aVal)
+{
+  nsCString val;
+  nsresult rv = Preferences::GetCString(aPref, &val);
+  if (NS_SUCCEEDED(rv)) {
+    aVal = val;
+  }
+  return rv;
+}
+
+/* static */
+CameraPreferences::Pref CameraPreferences::sPrefs[] = {
+  {
+    "camera.control.test.enabled",
+    kPrefValueIsCString,
+    { &sPrefTestEnabled }
+  },
+  {
+    "camera.control.test.hardware",
+    kPrefValueIsCString,
+    { &sPrefHardwareTest }
+  },
+#ifdef MOZ_B2G
+  {
+    "camera.control.test.hardware.gonk.parameters",
+    kPrefValueIsCString,
+    { &sPrefGonkParameters }
+  },
+#endif
+  {
+    "camera.control.test.method.error",
+    kPrefValueIsNSResult,
+    { &sPrefCameraControlMethodErrorOverride }
+  },
+  {
+    "camera.control.test.async.error",
+    kPrefValueIsNSResult,
+    { &sPrefCameraControlAsyncErrorOverride }
+  },
+};
+
+/* static */
+uint32_t
+CameraPreferences::PrefToIndex(const char* aPref)
+{
+  for (uint32_t i = 0; i < ArrayLength(sPrefs); ++i) {
+    if (strcmp(aPref, sPrefs[i].mPref) == 0) {
+      return i;
+    }
+  }
+  return kPrefNotFound;
+}
+
+/* static */
+void
+CameraPreferences::PreferenceChanged(const char* aPref, void* aClosure)
+{
+  MonitorAutoLock mon(*sPrefMonitor);
+
+  uint32_t i = PrefToIndex(aPref);
+  if (i == kPrefNotFound) {
+    DOM_CAMERA_LOGE("Preference '%s' is not tracked by CameraPreferences\n", aPref);
+    return;
+  }
+
+  Pref& p = sPrefs[i];
+  nsresult rv;
+  switch (p.mValueType) {
+    case kPrefValueIsNSResult:
+      {
+        nsresult& v = *p.mValue.mAsNsResult;
+        rv = UpdatePref(aPref, v);
+        if (NS_SUCCEEDED(rv)) {
+          DOM_CAMERA_LOGI("Preference '%s' has changed, 0x%x\n", aPref, v);
+        }
+      }
+      break;
+
+    case kPrefValueIsCString:
+      {
+        nsCString& v = **p.mValue.mAsCString;
+        rv = UpdatePref(aPref, v);
+        if (NS_SUCCEEDED(rv)) {
+          DOM_CAMERA_LOGI("Preference '%s' has changed, '%s'\n", aPref, v.get());
+        }
+      }
+      break;
+
+    default:
+      MOZ_ASSERT_UNREACHABLE("Unhandled preference value type!");
+      return;
+  }
+
+#ifdef DEBUG
+  if (NS_FAILED(rv)) {
+    nsCString msg;
+    msg.AppendPrintf("Failed to update pref '%s' (0x%x)\n", aPref, rv);
+    NS_WARNING(msg.get());
+  }
+#endif
+}
+
+/* static */
+bool
+CameraPreferences::Initialize()
+{
+  DOM_CAMERA_LOGI("Initializing camera preference callbacks\n");
+
+  nsresult rv;
+
+  sPrefMonitor = new Monitor("CameraPreferences.sPrefMonitor");
+
+  sPrefTestEnabled = new nsCString();
+  sPrefHardwareTest = new nsCString();
+  sPrefGonkParameters = new nsCString();
+
+  for (uint32_t i = 0; i < ArrayLength(sPrefs); ++i) {
+    rv = Preferences::RegisterCallbackAndCall(CameraPreferences::PreferenceChanged,
+                                              sPrefs[i].mPref);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return false;
+    }
+  }
+
+  DOM_CAMERA_LOGI("Camera preferences initialized\n");
+  return true;
+}
+
+/* static */
+void
+CameraPreferences::Shutdown()
+{
+  DOM_CAMERA_LOGI("Shutting down camera preference callbacks\n");
+
+  for (uint32_t i = 0; i < ArrayLength(sPrefs); ++i) {
+    Preferences::UnregisterCallback(CameraPreferences::PreferenceChanged,
+                                    sPrefs[i].mPref);
+  }
+
+  sPrefTestEnabled = nullptr;
+  sPrefHardwareTest = nullptr;
+  sPrefGonkParameters = nullptr;
+  sPrefMonitor = nullptr;
+
+  DOM_CAMERA_LOGI("Camera preferences shut down\n");
+}
+
+/* static */
+bool
+CameraPreferences::GetPref(const char* aPref, nsACString& aVal)
+{
+  MOZ_ASSERT(sPrefMonitor, "sPrefMonitor missing in CameraPreferences::GetPref()");
+  MonitorAutoLock mon(*sPrefMonitor);
+
+  uint32_t i = PrefToIndex(aPref);
+  if (i == kPrefNotFound || i >= ArrayLength(sPrefs)) {
+    DOM_CAMERA_LOGW("Preference '%s' is not tracked by CameraPreferences\n", aPref);
+    return false;
+  }
+  if (sPrefs[i].mValueType != kPrefValueIsCString) {
+    DOM_CAMERA_LOGW("Preference '%s' is not a string type\n", aPref);
+    return false;
+  }
+
+  StaticAutoPtr<nsCString>* s = sPrefs[i].mValue.mAsCString;
+  if (!*s) {
+    DOM_CAMERA_LOGE("Preference '%s' cache is not initialized\n", aPref);
+    return false;
+  }
+  if ((*s)->IsEmpty()) {
+    DOM_CAMERA_LOGI("Preference '%s' is not set\n", aPref);
+    return false;
+  }
+
+  DOM_CAMERA_LOGI("Preference '%s', got '%s'\n", aPref, (*s)->get());
+  aVal = **s;
+  return true;
+}
+
+/* static */
+bool
+CameraPreferences::GetPref(const char* aPref, nsresult& aVal)
+{
+  MOZ_ASSERT(sPrefMonitor, "sPrefMonitor missing in CameraPreferences::GetPref()");
+  MonitorAutoLock mon(*sPrefMonitor);
+
+  uint32_t i = PrefToIndex(aPref);
+  if (i == kPrefNotFound || i >= ArrayLength(sPrefs)) {
+    DOM_CAMERA_LOGW("Preference '%s' is not tracked by CameraPreferences\n", aPref);
+    return false;
+  }
+  if (sPrefs[i].mValueType != kPrefValueIsNSResult) {
+    DOM_CAMERA_LOGW("Preference '%s' is not an nsresult type\n", aPref);
+    return false;
+  }
+
+  nsresult v = *sPrefs[i].mValue.mAsNsResult;
+  if (v == NS_OK) {
+    DOM_CAMERA_LOGI("Preference '%s' is not set\n", aPref);
+    return false;
+  }
+
+  DOM_CAMERA_LOGI("Preference '%s', got 0x%x\n", aPref, v);
+  aVal = v;
+  return true;
+}
diff --git a/dom/camera/CameraPreferences.h b/dom/camera/CameraPreferences.h
new file mode 100644
index 00000000000..f1a59522ac2
--- /dev/null
+++ b/dom/camera/CameraPreferences.h
@@ -0,0 +1,67 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_CAMERA_CAMERAPREFERENCES_H
+#define DOM_CAMERA_CAMERAPREFERENCES_H
+
+#include "nsString.h"
+
+namespace mozilla {
+
+template<class T> class StaticAutoPtr;
+
+class CameraPreferences
+{
+public:
+  static bool Initialize();
+  static void Shutdown();
+
+  static bool GetPref(const char* aPref, nsACString& aVal);
+  static bool GetPref(const char* aPref, nsresult& aVal);
+
+protected:
+  static const uint32_t kPrefNotFound = UINT32_MAX;
+  static uint32_t PrefToIndex(const char* aPref);
+
+  static void PreferenceChanged(const char* aPref, void* aClosure);
+  static nsresult UpdatePref(const char* aPref, nsresult& aVar);
+  static nsresult UpdatePref(const char* aPref, nsACString& aVar);
+
+  enum PrefValueType {
+    kPrefValueIsNSResult,
+    kPrefValueIsCString
+  };
+  struct Pref {
+    const char* const           mPref;
+    PrefValueType               mValueType;
+    union {
+      // The 'mAsVoid' member must be first and is required to allow 'mValue'
+      // to be initialized with any pointer type, as not all of our platforms
+      // support the use of designated initializers; in their absence, only
+      // the first element of a union can be statically initialized, and
+      // 'void*' lets us stuff any pointer type into it.
+      void*                     mAsVoid;
+      StaticAutoPtr<nsCString>* mAsCString;
+      nsresult*                 mAsNsResult;
+    } mValue;
+  };
+  static Pref sPrefs[];
+
+  static StaticAutoPtr<nsCString> sPrefTestEnabled;
+  static StaticAutoPtr<nsCString> sPrefHardwareTest;
+  static StaticAutoPtr<nsCString> sPrefGonkParameters;
+
+  static nsresult sPrefCameraControlMethodErrorOverride;
+  static nsresult sPrefCameraControlAsyncErrorOverride;
+
+private:
+  // static class only
+  CameraPreferences();
+  ~CameraPreferences();
+};
+
+} // namespace mozilla
+
+#endif // DOM_CAMERA_CAMERAPREFERENCES_H
diff --git a/dom/camera/GonkCameraHwMgr.cpp b/dom/camera/GonkCameraHwMgr.cpp
index c1eb3dee8fc..96c3628c51a 100644
--- a/dom/camera/GonkCameraHwMgr.cpp
+++ b/dom/camera/GonkCameraHwMgr.cpp
@@ -23,7 +23,7 @@
 #include "base/basictypes.h"
 #include "nsDebug.h"
 #include "mozilla/layers/TextureClient.h"
-#include "mozilla/Preferences.h"
+#include "CameraPreferences.h"
 #include "mozilla/RefPtr.h"
 #include "GonkCameraControl.h"
 #include "GonkNativeWindow.h"
@@ -212,8 +212,8 @@ GonkCameraHardware::Connect(mozilla::nsGonkCameraControl* aTarget, uint32_t aCam
     return nullptr;
   }
 
-  const nsAdoptingCString& test =
-    mozilla::Preferences::GetCString("camera.control.test.enabled");
+  nsCString test;
+  CameraPreferences::GetPref("camera.control.test.enabled", test);
   sp<GonkCameraHardware> cameraHardware;
   if (test.EqualsASCII("hardware")) {
     NS_WARNING("Using test Gonk hardware layer");
diff --git a/dom/camera/GonkCameraManager.cpp b/dom/camera/GonkCameraManager.cpp
index febb31a888a..41d0b6d7746 100644
--- a/dom/camera/GonkCameraManager.cpp
+++ b/dom/camera/GonkCameraManager.cpp
@@ -20,7 +20,7 @@
 
 #include "CameraCommon.h"
 #include "GonkCameraControl.h"
-#include "mozilla/Preferences.h"
+#include "CameraPreferences.h"
 #include "TestGonkCameraControl.h"
 
 using namespace mozilla;
@@ -117,13 +117,12 @@ ICameraControl::GetListOfCameras(nsTArray<nsString>& aList)
   return NS_OK;
 }
 
-static const char* sTestModeEnabled = "camera.control.test.enabled";
-
 // implementation-specific camera factory
 already_AddRefed<ICameraControl>
 ICameraControl::Create(uint32_t aCameraId)
 {
-  const nsAdoptingCString& test = Preferences::GetCString(sTestModeEnabled);
+  nsCString test;
+  CameraPreferences::GetPref("camera.control.test.enabled", test);
   nsRefPtr<nsGonkCameraControl> control;
   if (test.EqualsASCII("control")) {
     NS_WARNING("Using test CameraControl layer");
diff --git a/dom/camera/TestGonkCameraControl.cpp b/dom/camera/TestGonkCameraControl.cpp
index d78504045a2..67518a23dac 100644
--- a/dom/camera/TestGonkCameraControl.cpp
+++ b/dom/camera/TestGonkCameraControl.cpp
@@ -15,13 +15,10 @@
  */
 
 #include "TestGonkCameraControl.h"
-#include "mozilla/Preferences.h"
+#include "CameraPreferences.h"
 
 using namespace mozilla;
 
-static const char* sMethodErrorOverride = "camera.control.test.method.error";
-static const char* sAsyncErrorOverride = "camera.control.test.async.error";
-
 TestGonkCameraControl::TestGonkCameraControl(uint32_t aCameraId)
   : nsGonkCameraControl(aCameraId)
 {
@@ -37,9 +34,8 @@ TestGonkCameraControl::~TestGonkCameraControl()
 nsresult
 TestGonkCameraControl::ForceMethodFailWithCodeInternal(const char* aFile, int aLine)
 {
-  nsresult rv =
-    static_cast<nsresult>(Preferences::GetInt(sMethodErrorOverride,
-                                              static_cast<int32_t>(NS_OK)));
+  nsresult rv = NS_OK;
+  CameraPreferences::GetPref("camera.control.test.method.error", rv);
   if (NS_FAILED(rv)) {
     DOM_CAMERA_LOGI("[%s:%d] CameraControl method error override: 0x%x\n",
       aFile, aLine, rv);
@@ -50,9 +46,8 @@ TestGonkCameraControl::ForceMethodFailWithCodeInternal(const char* aFile, int aL
 nsresult
 TestGonkCameraControl::ForceAsyncFailWithCodeInternal(const char* aFile, int aLine)
 {
-  nsresult rv =
-    static_cast<nsresult>(Preferences::GetInt(sAsyncErrorOverride,
-                                              static_cast<int32_t>(NS_OK)));
+  nsresult rv = NS_OK;
+  CameraPreferences::GetPref("camera.control.test.async.error", rv);
   if (NS_FAILED(rv)) {
     DOM_CAMERA_LOGI("[%s:%d] CameraControl async error override: 0x%x\n",
       aFile, aLine, rv);
diff --git a/dom/camera/TestGonkCameraHardware.cpp b/dom/camera/TestGonkCameraHardware.cpp
index e4f83685151..418388e2247 100644
--- a/dom/camera/TestGonkCameraHardware.cpp
+++ b/dom/camera/TestGonkCameraHardware.cpp
@@ -16,7 +16,7 @@
 
 #include "TestGonkCameraHardware.h"
 
-#include "mozilla/Preferences.h"
+#include "CameraPreferences.h"
 #include "nsThreadUtils.h"
 
 using namespace android;
@@ -52,7 +52,8 @@ TestGonkCameraHardware::Init()
 const nsCString
 TestGonkCameraHardware::TestCase()
 {
-  const nsCString test = Preferences::GetCString("camera.control.test.hardware");
+  nsCString test;
+  CameraPreferences::GetPref("camera.control.test.hardware", test);
   return test;
 }
 
@@ -77,7 +78,8 @@ TestGonkCameraHardware::GetExtraParameters()
    * may contain equals signs or semicolons. We don't enforce that here
    * so that we can also test correct handling of improperly-formatted values.
    */
-  const nsCString parameters = Preferences::GetCString("camera.control.test.hardware.gonk.parameters");
+  nsCString parameters;
+  CameraPreferences::GetPref("camera.control.test.hardware.gonk.parameters", parameters);
   DOM_CAMERA_LOGA("TestGonkCameraHardware : extra-parameters '%s'\n",
     parameters.get());
   return parameters;
diff --git a/dom/camera/moz.build b/dom/camera/moz.build
index 6acf7ded68c..148aa5d8d1d 100644
--- a/dom/camera/moz.build
+++ b/dom/camera/moz.build
@@ -9,13 +9,13 @@ if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'gonk':
 
 EXPORTS += [
     'CameraCommon.h',
-    'CameraPreviewMediaStream.h',
+    'CameraPreferences.h',
     'DOMCameraManager.h',
-    'GonkCameraControl.h',
 ]
 
 SOURCES += [
     'CameraControlImpl.cpp',
+    'CameraPreferences.cpp',
     'CameraPreviewMediaStream.cpp',
     'CameraRecorderProfiles.cpp',
     'DOMCameraCapabilities.cpp',
diff --git a/layout/build/nsLayoutStatics.cpp b/layout/build/nsLayoutStatics.cpp
index 35a3756e817..716f0317035 100644
--- a/layout/build/nsLayoutStatics.cpp
+++ b/layout/build/nsLayoutStatics.cpp
@@ -132,6 +132,7 @@ using namespace mozilla::system;
 #include "mozilla/IMEStateManager.h"
 #include "nsDocument.h"
 #include "mozilla/dom/HTMLVideoElement.h"
+#include "CameraPreferences.h"
 
 using namespace mozilla;
 using namespace mozilla::net;
@@ -296,6 +297,8 @@ nsLayoutStatics::Initialize()
 
   CounterStyleManager::InitializeBuiltinCounterStyles();
 
+  CameraPreferences::Initialize();
+
   return NS_OK;
 }
 
@@ -426,4 +429,6 @@ nsLayoutStatics::Shutdown()
   nsDocument::XPCOMShutdown();
 
   CacheObserver::Shutdown();
+
+  CameraPreferences::Shutdown();
 }