Bug 924194 - Make gfxQuartzNativeDrawing::BeginNativeDrawing able to handle DrawTargets with a different backend than BACKEND_COREGRAPHICS (e.g. BACKEND_CAIRO). r=jrmuizel

--HG--
extra : rebase_source : d284993fae8681854b73f4d9f935427b98731dfa

gfx/thebes/gfxQuartzNativeDrawing.cpp

@@ -35,32 +35,37 @@ gfxQuartzNativeDrawing::BeginNativeDrawing()
 {
     NS_ASSERTION(!mQuartzSurface, "BeginNativeDrawing called when drawing already in progress");
 
+    gfxPoint deviceOffset;
+    nsRefPtr<gfxASurface> surf;
+
     if (!mContext->IsCairo()) {
       DrawTarget *dt = mContext->GetDrawTarget();
-      if (mContext->GetDrawTarget()->IsDualDrawTarget()) {
-        IntSize backingSize(NSToIntFloor(mNativeRect.width * mBackingScale),
-                            NSToIntFloor(mNativeRect.height * mBackingScale));
+      if (dt->GetType() == BACKEND_COREGRAPHICS) {
+        if (dt->IsDualDrawTarget()) {
+          IntSize backingSize(NSToIntFloor(mNativeRect.width * mBackingScale),
+                              NSToIntFloor(mNativeRect.height * mBackingScale));
 
-       if (backingSize.IsEmpty())
-          return nullptr;
+         if (backingSize.IsEmpty())
+            return nullptr;
 
-        mDrawTarget = Factory::CreateDrawTarget(BACKEND_COREGRAPHICS, backingSize, FORMAT_B8G8R8A8);
+          mDrawTarget = Factory::CreateDrawTarget(BACKEND_COREGRAPHICS, backingSize, FORMAT_B8G8R8A8);
 
-        Matrix transform;
-        transform.Scale(mBackingScale, mBackingScale);
-        transform.Translate(-mNativeRect.x, -mNativeRect.y);
+          Matrix transform;
+          transform.Scale(mBackingScale, mBackingScale);
+          transform.Translate(-mNativeRect.x, -mNativeRect.y);
 
-        mDrawTarget->SetTransform(transform);
-        dt = mDrawTarget;
+          mDrawTarget->SetTransform(transform);
+          dt = mDrawTarget;
+        }
+
+        mCGContext = mBorrowedContext.Init(dt);
+        MOZ_ASSERT(mCGContext);
+        return mCGContext;
       }
-
-      mCGContext = mBorrowedContext.Init(dt);
-      MOZ_ASSERT(mCGContext);
-      return mCGContext;
+      surf = gfxPlatform::GetPlatform()->GetThebesSurfaceForDrawTarget(dt);
+    } else {
+      surf = mContext->CurrentSurface(&deviceOffset.x, &deviceOffset.y);
     }
-
-    gfxPoint deviceOffset;
-    nsRefPtr<gfxASurface> surf = mContext->CurrentSurface(&deviceOffset.x, &deviceOffset.y);
     if (!surf || surf->CairoStatus())
         return nullptr;