From 3184ccc8f2f8ebe21f6839d9ea48c4b753292c8f Mon Sep 17 00:00:00 2001
From: Alexander Surkov <surkov.alexander@gmail.com>
Date: Thu, 21 Jul 2011 13:37:32 +0900
Subject: [PATCH] Bug 671510 - make sure accessible tree is created for content
 processes, r=jones.chris.g, sr=Olli.Pettay, f=felipc

---
 dom/ipc/ContentChild.cpp  | 16 ++++++++++++++++
 dom/ipc/ContentChild.h    |  2 ++
 dom/ipc/ContentParent.cpp | 23 +++++++++++++++++++++++
 dom/ipc/PContent.ipdl     |  5 +++++
 4 files changed, 46 insertions(+)

diff --git a/dom/ipc/ContentChild.cpp b/dom/ipc/ContentChild.cpp
index c6148a23789..7df66b27877 100644
--- a/dom/ipc/ContentChild.cpp
+++ b/dom/ipc/ContentChild.cpp
@@ -104,6 +104,10 @@
 #define getpid _getpid
 #endif
 
+#ifdef ACCESSIBILITY
+#include "nsIAccessibilityService.h"
+#endif
+
 using namespace mozilla::ipc;
 using namespace mozilla::net;
 using namespace mozilla::places;
@@ -734,6 +738,18 @@ ContentChild::RecvFlushMemory(const nsString& reason)
   return true;
 }
 
+bool
+ContentChild::RecvActivateA11y()
+{
+#ifdef ACCESSIBILITY
+    // Start accessibility in content process if it's running in chrome
+    // process.
+    nsCOMPtr<nsIAccessibilityService> accService =
+        do_GetService("@mozilla.org/accessibilityService;1");
+#endif
+    return true;
+}
+
 nsString&
 ContentChild::GetIndexedDBPath()
 {
diff --git a/dom/ipc/ContentChild.h b/dom/ipc/ContentChild.h
index ab3000f49bc..db220eeaeec 100644
--- a/dom/ipc/ContentChild.h
+++ b/dom/ipc/ContentChild.h
@@ -146,6 +146,8 @@ public:
 
     virtual bool RecvFlushMemory(const nsString& reason);
 
+    virtual bool RecvActivateA11y();
+
 #ifdef ANDROID
     gfxIntSize GetScreenSize() { return mScreenSize; }
 #endif
diff --git a/dom/ipc/ContentParent.cpp b/dom/ipc/ContentParent.cpp
index 45758f7b509..6c9cc16940e 100644
--- a/dom/ipc/ContentParent.cpp
+++ b/dom/ipc/ContentParent.cpp
@@ -62,6 +62,7 @@
 #include "nsExternalHelperAppService.h"
 #include "nsCExternalHandlerService.h"
 #include "nsFrameMessageManager.h"
+#include "nsIPresShell.h"
 #include "nsIAlertsService.h"
 #include "nsToolkitCompsCID.h"
 #include "nsIDOMGeoGeolocation.h"
@@ -179,6 +180,9 @@ ContentParent::Init()
         obs->AddObserver(this, NS_IPC_IOSERVICE_SET_OFFLINE_TOPIC, PR_FALSE);
         obs->AddObserver(this, "child-memory-reporter-request", PR_FALSE);
         obs->AddObserver(this, "memory-pressure", PR_FALSE);
+#ifdef ACCESSIBILITY
+        obs->AddObserver(this, "a11y-init-or-shutdown", PR_FALSE);
+#endif
     }
     nsCOMPtr<nsIPrefBranch2> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
     if (prefs) {
@@ -193,6 +197,14 @@ ContentParent::Init()
     if (obs) {
         obs->NotifyObservers(nsnull, "ipc:content-created", nsnull);
     }
+
+#ifdef ACCESSIBILITY
+    // If accessibility is running in chrome process then start it in content
+    // process.
+    if (nsIPresShell::IsAccessibilityActive()) {
+        SendActivateA11y();
+    }
+#endif
 }
 
 void
@@ -257,6 +269,9 @@ ContentParent::ActorDestroy(ActorDestroyReason why)
         obs->RemoveObserver(static_cast<nsIObserver*>(this), "memory-pressure");
         obs->RemoveObserver(static_cast<nsIObserver*>(this), "child-memory-reporter-request");
         obs->RemoveObserver(static_cast<nsIObserver*>(this), NS_IPC_IOSERVICE_SET_OFFLINE_TOPIC);
+#ifdef ACCESSIBILITY
+        obs->RemoveObserver(static_cast<nsIObserver*>(this), "a11y-init-or-shutdown");
+#endif
     }
 
     // clear the child memory reporters
@@ -656,6 +671,14 @@ ContentParent::Observe(nsISupports* aSubject,
     else if (!strcmp(aTopic, "child-memory-reporter-request")) {
         SendPMemoryReportRequestConstructor();
     }
+#ifdef ACCESSIBILITY
+    // Make sure accessibility is running in content process when accessibility
+    // gets initiated in chrome process.
+    else if (aData && (*aData == '1') &&
+             !strcmp(aTopic, "a11y-init-or-shutdown")) {
+        SendActivateA11y();
+    }
+#endif
 
     return NS_OK;
 }
diff --git a/dom/ipc/PContent.ipdl b/dom/ipc/PContent.ipdl
index 597a2e12a80..f158b72911e 100644
--- a/dom/ipc/PContent.ipdl
+++ b/dom/ipc/PContent.ipdl
@@ -129,6 +129,11 @@ child:
 
     FlushMemory(nsString reason);
 
+    /**
+     * Start accessibility engine in content process.
+     */
+    ActivateA11y();
+
 parent:
     PNecko();
     PCrashReporter();