Fix for bug 762654 (Switch the Azure 2d canvas context to new DOM bindings). r=bz.

content/canvas/public/nsICanvasRenderingContextInternal.h

@@ -129,6 +129,14 @@ protected:
   nsRefPtr<nsHTMLCanvasElement> mCanvasElement;
 };
 
+namespace mozilla {
+namespace dom {
+
+extern bool AzureCanvasEnabled();
+
+}
+}
+
 NS_DEFINE_STATIC_IID_ACCESSOR(nsICanvasRenderingContextInternal,
                               NS_ICANVASRENDERINGCONTEXTINTERNAL_IID)
 

content/canvas/src/nsCanvasRenderingContext2DAzure.cpp

@@ -95,6 +95,7 @@
 #include "mozilla/dom/BindingUtils.h"
 #include "nsHTMLImageElement.h"
 #include "nsHTMLVideoElement.h"
+#include "mozilla/dom/CanvasRenderingContext2DBinding.h"
 
 #ifdef XP_WIN
 #include "gfxWindowsPlatform.h"
@@ -545,19 +546,51 @@ PRUint32 nsCanvasRenderingContext2DAzure::sNumLivingContexts = 0;
 PRUint8 (*nsCanvasRenderingContext2DAzure::sUnpremultiplyTable)[256] = nsnull;
 PRUint8 (*nsCanvasRenderingContext2DAzure::sPremultiplyTable)[256] = nsnull;
 
+namespace mozilla {
+namespace dom {
+
+static bool
+AzureCanvasEnabledOnPlatform()
+{
+#ifdef XP_WIN
+  if (gfxWindowsPlatform::GetPlatform()->GetRenderMode() !=
+      gfxWindowsPlatform::RENDER_DIRECT2D ||
+      !gfxWindowsPlatform::GetPlatform()->DWriteEnabled()) {
+    static bool checkedPref = false;
+    static bool preferSkia;
+    if (!checkedPref) {
+      preferSkia = Preferences::GetBool("gfx.canvas.azure.prefer-skia", false);
+      checkedPref = true;
+    }
+    return preferSkia;
+  }
+#elif !defined(XP_MACOSX) && !defined(ANDROID) && !defined(LINUX)
+  return false;
+#endif
+  return true;
+}
+
+bool
+AzureCanvasEnabled()
+{
+  static bool checkedPref = false;
+  static bool azureEnabled;
+  if (!checkedPref) {
+    azureEnabled = Preferences::GetBool("gfx.canvas.azure.enabled", false);
+    checkedPref = true;
+  }
+  return azureEnabled && AzureCanvasEnabledOnPlatform();
+}
+
+}
+}
+
 nsresult
 NS_NewCanvasRenderingContext2DAzure(nsIDOMCanvasRenderingContext2D** aResult)
 {
-#ifdef XP_WIN
-  if ((gfxWindowsPlatform::GetPlatform()->GetRenderMode() !=
-      gfxWindowsPlatform::RENDER_DIRECT2D ||
-      !gfxWindowsPlatform::GetPlatform()->DWriteEnabled()) &&
-      !Preferences::GetBool("gfx.canvas.azure.prefer-skia", false)) {
+  if (!AzureCanvasEnabledOnPlatform()) {
     return NS_ERROR_NOT_AVAILABLE;
   }
-#elif !defined(XP_MACOSX) && !defined(ANDROID) && !defined(LINUX)
-  return NS_ERROR_NOT_AVAILABLE;
-#endif
 
   nsRefPtr<nsIDOMCanvasRenderingContext2D> ctx = new nsCanvasRenderingContext2DAzure();
   if (!ctx)
@@ -575,6 +608,7 @@ nsCanvasRenderingContext2DAzure::nsCanvasRenderingContext2DAzure()
   , mInvalidateCount(0)
 {
   sNumLivingContexts++;
+  SetIsDOMBinding();
 }
 
 nsCanvasRenderingContext2DAzure::~nsCanvasRenderingContext2DAzure()
@@ -593,6 +627,13 @@ nsCanvasRenderingContext2DAzure::~nsCanvasRenderingContext2DAzure()
   }
 }
 
+JSObject*
+nsCanvasRenderingContext2DAzure::WrapObject(JSContext *cx, JSObject *scope,
+                                            bool *triedToWrap)
+{
+  return CanvasRenderingContext2DBinding::Wrap(cx, scope, this, triedToWrap);
+}
+
 bool
 nsCanvasRenderingContext2DAzure::ParseColor(const nsAString& aString,
                                             nscolor* aColor)

content/canvas/src/nsCanvasRenderingContext2DAzure.h

@@ -138,6 +138,9 @@ public:
   nsCanvasRenderingContext2DAzure();
   virtual ~nsCanvasRenderingContext2DAzure();
 
+  virtual JSObject* WrapObject(JSContext *cx, JSObject *scope,
+                               bool *triedToWrap);
+
   nsHTMLCanvasElement* GetCanvas() const
   {
     return mCanvasElement;

content/canvas/test/test_canvas.html

@@ -19548,7 +19548,11 @@ ok(window.CanvasRenderingContext2D.prototype, "window.CanvasRenderingContext2D.p
 window.CanvasRenderingContext2D.prototype.fill = 1;
 ok(window.CanvasRenderingContext2D.prototype.fill === 1, "window.CanvasRenderingContext2D.prototype.fill === 1");
 delete window.CanvasRenderingContext2D.prototype.fill;
-todo(window.CanvasRenderingContext2D.prototype.fill === undefined, "window.CanvasRenderingContext2D.prototype.fill === undefined");
+if (IsAzureEnabled()) {
+  ok(window.CanvasRenderingContext2D.prototype.fill === undefined, "window.CanvasRenderingContext2D.prototype.fill === undefined");
+} else {
+  todo(window.CanvasRenderingContext2D.prototype.fill === undefined, "window.CanvasRenderingContext2D.prototype.fill === undefined");
+}
 
 //restore the original method to ensure that other tests can run successfully
 window.CanvasRenderingContext2D.prototype.fill = fill;

content/html/content/src/nsHTMLCanvasElement.cpp

@@ -768,12 +768,8 @@ nsresult
 NS_NewCanvasRenderingContext2D(nsIDOMCanvasRenderingContext2D** aResult)
 {
   Telemetry::Accumulate(Telemetry::CANVAS_2D_USED, 1);
-  if (Preferences::GetBool("gfx.canvas.azure.enabled", false)) {
-    nsresult rv = NS_NewCanvasRenderingContext2DAzure(aResult);
-    // If Azure fails, fall back to a classic canvas.
-    if (NS_SUCCEEDED(rv)) {
-      return rv;
-    }
+  if (AzureCanvasEnabled()) {
+    return NS_NewCanvasRenderingContext2DAzure(aResult);
   }
 
   return NS_NewCanvasRenderingContext2DThebes(aResult);

dom/base/nsDOMClassInfo.cpp

@@ -534,6 +534,7 @@ using mozilla::dom::indexedDB::IDBWrapperCache;
 
 #undef None // something included above defines this preprocessor symbol, maybe Xlib headers
 #include "WebGLContext.h"
+#include "nsICanvasRenderingContextInternal.h"
 
 using namespace mozilla;
 using namespace mozilla::dom;
@@ -4590,6 +4591,10 @@ nsDOMClassInfo::Init()
   // Non-proxy bindings
   mozilla::dom::Register(nameSpaceManager);
 
+  if (!AzureCanvasEnabled()) {
+    nameSpaceManager->RegisterDefineDOMInterface(NS_LITERAL_STRING("CanvasRenderingContext2D"), NULL);
+  }
+
   sIsInitialized = true;
 
   return NS_OK;