Bug 968923 - part 5b - add nsIDOMWindowUtils::forceUseCounterFlush; r=bz

Use counter submission normally happens at document destruction.  For
testing use counters, however, we need to have use counters updated in
telemetry at deterministic points.  Therefore, we provide a method on
nsIDOMWindowUtils that forces use counters out to telemetry so we can
examine them.

dom/base/nsDOMWindowUtils.cpp

@@ -103,6 +103,9 @@
 #include "nsIStyleSheetService.h"
 #include "nsContentPermissionHelper.h"
 #include "nsNetUtil.h"
+#include "nsDocument.h"
+#include "HTMLImageElement.h"
+#include "mozilla/css/ImageLoader.h"
 
 #ifdef XP_WIN
 #undef GetClassName
@@ -3919,6 +3922,30 @@ nsDOMWindowUtils::LeaveChaosMode()
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsDOMWindowUtils::ForceUseCounterFlush(nsIDOMNode *aNode)
+{
+  MOZ_RELEASE_ASSERT(nsContentUtils::IsCallerChrome());
+  NS_ENSURE_ARG_POINTER(aNode);
+
+  if (nsCOMPtr<nsIDocument> doc = do_QueryInterface(aNode)) {
+    mozilla::css::ImageLoader* loader = doc->StyleImageLoader();
+    loader->FlushUseCounters();
+
+    static_cast<nsDocument*>(doc.get())->ReportUseCounters();
+    return NS_OK;
+  }
+
+  if (nsCOMPtr<nsIContent> content = do_QueryInterface(aNode)) {
+    if (HTMLImageElement* img = HTMLImageElement::FromContent(content)) {
+      img->FlushUseCounters();
+      return NS_OK;
+    }
+  }
+
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsDOMWindowUtils::HasRuleProcessorUsedByMultipleStyleSets(uint32_t aSheetType,
                                                           bool* aRetVal)

dom/html/HTMLImageElement.cpp

@@ -11,6 +11,7 @@
 #include "nsPresContext.h"
 #include "nsMappedAttributes.h"
 #include "nsSize.h"
+#include "nsDocument.h"
 #include "nsIDocument.h"
 #include "nsIDOMMutationEvent.h"
 #include "nsIScriptContext.h"
@@ -27,6 +28,7 @@
 #include "mozilla/dom/HTMLFormElement.h"
 #include "nsAttrValueOrString.h"
 #include "imgLoader.h"
+#include "Image.h"
 
 // Responsive images!
 #include "mozilla/dom/HTMLSourceElement.h"
@@ -1301,6 +1303,18 @@ HTMLImageElement::MediaFeatureValuesChanged()
   QueueImageLoadTask();
 }
 
+void
+HTMLImageElement::FlushUseCounters()
+{
+  nsCOMPtr<imgIRequest> request;
+  GetRequest(CURRENT_REQUEST, getter_AddRefs(request));
+
+  nsCOMPtr<imgIContainer> container;
+  request->GetImage(getter_AddRefs(container));
+
+  static_cast<image::Image*>(container.get())->ReportUseCounters();
+}
+
 } // namespace dom
 } // namespace mozilla
 

dom/html/HTMLImageElement.h

@@ -265,6 +265,12 @@ public:
                                 const nsAString& aMediaAttr,
                                 nsAString& aResult);
 
+  /**
+   * If this image's src pointers to an SVG document, flush the SVG document's
+   * use counters to telemetry.  Only used for testing purposes.
+   */
+  void FlushUseCounters();
+
 protected:
   virtual ~HTMLImageElement();
 

dom/html/moz.build

@@ -236,6 +236,7 @@ LOCAL_INCLUDES += [
     '/dom/xul',
     '/editor/libeditor',
     '/editor/txmgr',
+    '/image',
     '/layout/forms',
     '/layout/generic',
     '/layout/style',

dom/interfaces/base/nsIDOMWindowUtils.idl

@@ -49,7 +49,7 @@ interface nsIJSRAIIHelper;
 interface nsIContentPermissionRequest;
 interface nsIObserver;
 
-[scriptable, uuid(47fa312b-2ad1-4b80-8a0a-c9822e2d1ec9)]
+[scriptable, uuid(e6d3ced6-fbce-4ea5-902a-c2055680d250)]
 interface nsIDOMWindowUtils : nsISupports {
 
   /**
@@ -1847,6 +1847,17 @@ interface nsIDOMWindowUtils : nsISupports {
    * @param aSheetType One of the nsIStyleSheetService.*_SHEET constants.
    */
   bool hasRuleProcessorUsedByMultipleStyleSets(in unsigned long aSheetType);
+
+  /*
+   * Force the use counters for the node's associated document(s) to be
+   * flushed to telemetry.  For example, a document node will flush its own
+   * counters and an image node with an SVG source will flush the SVG
+   * document's counters.  Normally, use counters are flushed to telemetry
+   * upon document destruction, but as document destruction is somewhat
+   * non-deterministic, we have this method here for more determinism when
+   * running tests.
+   */
+  void forceUseCounterFlush(in nsIDOMNode aNode);
 };
 
 [scriptable, uuid(c694e359-7227-4392-a138-33c0cc1f15a6)]

image/Image.h

@@ -229,6 +229,8 @@ public:
   virtual void SetHasError() = 0;
 
   virtual ImageURL* GetURI() = 0;
+
+  virtual void ReportUseCounters() { }
 };
 
 class ImageResource : public Image

image/VectorImage.cpp

@@ -32,6 +32,7 @@
 #include "SVGDocumentWrapper.h"
 #include "nsIDOMEventListener.h"
 #include "SurfaceCache.h"
+#include "nsDocument.h"
 
 // undef the GetCurrentTime macro defined in WinBase.h from the MS Platform SDK
 #undef GetCurrentTime
@@ -1259,6 +1260,15 @@ VectorImage::PropagateUseCounters(nsIDocument* aParentDocument)
   }
 }
 
+void
+VectorImage::ReportUseCounters()
+{
+  nsIDocument* doc = mSVGDocumentWrapper->GetDocument();
+  if (doc) {
+    static_cast<nsDocument*>(doc)->ReportUseCounters();
+  }
+}
+
 nsIntSize
 VectorImage::OptimalImageSizeForDest(const gfxSize& aDest,
                                      uint32_t aWhichFrame,

image/VectorImage.h

@@ -68,6 +68,8 @@ public:
   void OnSVGDocumentLoaded();
   void OnSVGDocumentError();
 
+  virtual void ReportUseCounters() override;
+
 protected:
   explicit VectorImage(ImageURL* aURI = nullptr);
   virtual ~VectorImage();

layout/style/ImageLoader.cpp

@@ -14,6 +14,7 @@
 #include "FrameLayerBuilder.h"
 #include "nsSVGEffects.h"
 #include "imgIContainer.h"
+#include "Image.h"
 
 namespace mozilla {
 namespace css {
@@ -510,5 +511,22 @@ ImageLoader::UnblockOnload(imgIRequest* aRequest)
   return NS_OK;
 }
 
+void
+ImageLoader::FlushUseCounters()
+{
+  for (auto iter = mImages.Iter(); !iter.Done(); iter.Next()) {
+    nsPtrHashKey<Image>* key = iter.Get();
+    ImageLoader::Image* image = key->GetKey();
+
+    imgIRequest* request = image->mRequests.GetWeak(mDocument);
+
+    nsCOMPtr<imgIContainer> container;
+    request->GetImage(getter_AddRefs(container));
+    if (container) {
+      static_cast<image::Image*>(container.get())->ReportUseCounters();
+    }
+  }
+}
+
 } // namespace css
 } // namespace mozilla

layout/style/ImageLoader.h

@@ -70,6 +70,8 @@ public:
 
   void DestroyRequest(imgIRequest* aRequest);
 
+  void FlushUseCounters();
+
 private:
   ~ImageLoader() {}
 

layout/style/moz.build

@@ -198,6 +198,7 @@ LOCAL_INCLUDES += [
     '/dom/html',
     '/dom/xbl',
     '/dom/xul',
+    '/image',
 ]
 
 JAR_MANIFESTS += ['jar.mn']