Make CreateRenderingContext() return error for a null surface and add error handling to callers. b=362201 r+sr=vladimir

gfx/src/thebes/nsThebesDeviceContext.cpp

@@ -321,6 +321,9 @@ nsThebesDeviceContext::CreateRenderingContext(nsIWidget *aWidget,
         nsRefPtr<gfxASurface> surface(aWidget->GetThebesSurface());
         if (surface)
             rv = pContext->Init(this, surface);
+        else
+            rv = NS_ERROR_FAILURE;
+
         if (NS_SUCCEEDED(rv)) {
             aContext = pContext;
             NS_ADDREF(aContext);

layout/base/nsPresShell.cpp

@@ -3410,7 +3410,9 @@ PresShell::CreateRenderingContext(nsIFrame *aFrame,
   }
   *aResult = result;
 
+  if (NS_SUCCEEDED(rv)) {
     result->Translate(offset.x, offset.y);
+  }
 
   return rv;
 }

layout/inspector/src/inFlasher.cpp

@@ -160,9 +160,11 @@ inFlasher::DrawElementOutline(nsIDOMElement* aElement)
 
   while (frame) {
     nsCOMPtr<nsIRenderingContext> rcontext;
+    nsresult rv =
       presShell->CreateRenderingContext(frame, getter_AddRefs(rcontext));
-    nsRect rect(nsPoint(0,0), frame->GetSize());
+    NS_ENSURE_SUCCESS(rv, rv);
 
+    nsRect rect(nsPoint(0,0), frame->GetSize());
     if (mInvert) {
       rcontext->InvertRect(rect);
     }

widget/src/cocoa/nsChildView.mm

@@ -1740,9 +1740,9 @@ nsChildView::Idle()
 gfxASurface*
 nsChildView::GetThebesSurface()
 {
-
   if (!mTempThebesSurface) {
     mTempThebesSurface = new gfxQuartzSurface(gfxSize(1, 1), gfxASurface::ImageFormatARGB32);
+    NS_ENSURE_TRUE(mTempThebesSurface.get(), nsnull); // OOM
   }
 
   gfxASurface *surf = mTempThebesSurface.get();