Add error messages for canvas creation failures

components/test_runner/pixel_dump.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/test_runner/pixel_dump.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 80 matching lines @@
   blink::WebSize page_size_in_pixels = dump_request->web_view->size();
   blink::WebFrame* web_frame = dump_request->web_view->mainFrame();
 
   int page_count = web_frame->printBegin(page_size_in_pixels);
   int totalHeight = page_count * (page_size_in_pixels.height + 1) - 1;
 
   bool is_opaque = false;
   sk_sp<SkCanvas> canvas(skia::TryCreateBitmapCanvas(
       page_size_in_pixels.width, totalHeight, is_opaque));
   if (!canvas) {
+    LOG(ERROR) << "Failed to create canvas width="
+               << page_size_in_pixels.width << " height=" << totalHeight;
     dump_request->callback.Run(SkBitmap());
     return;
   }
   web_frame->printPagesWithBoundaries(canvas.get(), page_size_in_pixels);
   web_frame->printEnd();
 
   DrawSelectionRect(*dump_request, canvas.get());
   const SkBitmap bitmap = skia::ReadPixels(canvas.get());
   dump_request->callback.Run(bitmap);
 }
@@ skipping 83 matching lines @@
 
   blink::WebImage image = static_cast<blink::WebMockClipboard*>(
                               blink::Platform::current()->clipboard())
                               ->readRawImage(blink::WebClipboard::Buffer());
   const SkBitmap& bitmap = image.getSkBitmap();
   SkAutoLockPixels autoLock(bitmap);
   callback.Run(bitmap);
 }
 
 }  // namespace test_runner