Bug 1034528, part 2 - Remove the Thebes backed gfxContext propagating code from nsCanvasFrame. r=Bas

layout/generic/nsCanvasFrame.cpp

@@ -249,16 +249,6 @@ nsDisplayCanvasBackgroundColor::WriteDebugInfo(nsACString& aTo)
 }
 #endif
 
-static void BlitSurface(gfxContext* aDest, const gfxRect& aRect, gfxASurface* aSource)
-{
-  aDest->Translate(gfxPoint(aRect.x, aRect.y));
-  aDest->SetSource(aSource);
-  aDest->NewPath();
-  aDest->Rectangle(gfxRect(0, 0, aRect.width, aRect.height));
-  aDest->Fill();
-  aDest->Translate(-gfxPoint(aRect.x, aRect.y));
-}
-
 static void BlitSurface(DrawTarget* aDest, const gfxRect& aRect, DrawTarget* aSource)
 {
   RefPtr<SourceSurface> source = aSource->Snapshot();
@@ -277,9 +267,7 @@ nsDisplayCanvasBackgroundImage::Paint(nsDisplayListBuilder* aBuilder,
 
   nsRefPtr<nsRenderingContext> context;
   nsRefPtr<gfxContext> dest = aCtx->ThebesContext();
-  nsRefPtr<gfxASurface> surf;
   RefPtr<DrawTarget> dt;
-  nsRefPtr<gfxContext> ctx;
   gfxRect destRect;
 #ifndef MOZ_GFX_OPTIMIZE_MOBILE
   if (IsSingleFixedPositionImage(aBuilder, bgClipRect, &destRect) &&
@@ -288,31 +276,15 @@ nsDisplayCanvasBackgroundImage::Paint(nsDisplayListBuilder* aBuilder,
     // Snap image rectangle to nearest pixel boundaries. This is the right way
     // to snap for this context, because we checked HasNonIntegerTranslation above.
     destRect.Round();
-    if (dest->IsCairo()) {
-      surf = static_cast<gfxASurface*>(Frame()->Properties().Get(nsIFrame::CachedBackgroundImage()));
-      nsRefPtr<gfxASurface> destSurf = dest->CurrentSurface();
-      if (surf && surf->GetType() == destSurf->GetType()) {
-        BlitSurface(dest, destRect, surf);
-        return;
-      }
-      surf = destSurf->CreateSimilarSurface(
-          gfxContentType::COLOR_ALPHA,
-          gfxIntSize(ceil(destRect.width), ceil(destRect.height)));
-    } else {
-      dt = static_cast<DrawTarget*>(Frame()->Properties().Get(nsIFrame::CachedBackgroundImageDT()));
-      DrawTarget* destDT = dest->GetDrawTarget();
-      if (dt) {
-        BlitSurface(destDT, destRect, dt);
-        return;
-      }
-      dt = destDT->CreateSimilarDrawTarget(IntSize(ceil(destRect.width), ceil(destRect.height)), SurfaceFormat::B8G8R8A8);
+    dt = static_cast<DrawTarget*>(Frame()->Properties().Get(nsIFrame::CachedBackgroundImageDT()));
+    DrawTarget* destDT = dest->GetDrawTarget();
+    if (dt) {
+      BlitSurface(destDT, destRect, dt);
+      return;
     }
-    if (surf || dt) {
-      if (surf) {
-        ctx = new gfxContext(surf);
-      } else {
-        ctx = new gfxContext(dt);
-      }
+    dt = destDT->CreateSimilarDrawTarget(IntSize(ceil(destRect.width), ceil(destRect.height)), SurfaceFormat::B8G8R8A8);
+    if (dt) {
+      nsRefPtr<gfxContext> ctx = new gfxContext(dt);
       ctx->Translate(-gfxPoint(destRect.x, destRect.y));
       context = new nsRenderingContext();
       context->Init(aCtx->DeviceContext(), ctx);
@@ -321,15 +293,10 @@ nsDisplayCanvasBackgroundImage::Paint(nsDisplayListBuilder* aBuilder,
 #endif
 
   PaintInternal(aBuilder,
-                (surf || dt) ? context.get() : aCtx,
-                (surf || dt) ? bgClipRect: mVisibleRect,
+                dt ? context.get() : aCtx,
+                dt ? bgClipRect: mVisibleRect,
                 &bgClipRect);
 
-  if (surf) {
-    BlitSurface(dest, destRect, surf);
-    frame->Properties().Set(nsIFrame::CachedBackgroundImage(),
-                            surf.forget().take());
-  }
   if (dt) {
     BlitSurface(dest->GetDrawTarget(), destRect, dt);
     frame->Properties().Set(nsIFrame::CachedBackgroundImageDT(), dt.forget().drop());