Track performance of toBlob and its complete timeout delay

third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 659 matching lines @@
         exceptionState.throwSecurityError("Tainted canvases may not be exported.");
         return;
     }
 
     if (!isPaintable()) {
         // If the canvas element's bitmap has no pixels
         Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&BlobCallback::handleEvent, callback, nullptr));
         return;
     }
 
+    double startTime = WTF::monotonicallyIncreasingTime();
     double quality = UndefinedQualityValue;
     if (!qualityArgument.isEmpty()) {
         v8::Local<v8::Value> v8Value = qualityArgument.v8Value();
         if (v8Value->IsNumber()) {
             quality = v8Value.As<v8::Number>()->Value();
         }
     }
 
     String encodingMimeType = toEncodingMimeType(mimeType, EncodeReasonToBlobCallback);
 
     ImageData* imageData = toImageData(BackBuffer, SnapshotReasonToBlob);
 
-    CanvasAsyncBlobCreator* asyncCreator = CanvasAsyncBlobCreator::create(imageData->data(), encodingMimeType, imageData->size(), callback);
+    CanvasAsyncBlobCreator* asyncCreator = CanvasAsyncBlobCreator::create(imageData->data(), encodingMimeType, imageData->size(), callback, startTime);
 
     bool useIdlePeriodScheduling = (encodingMimeType != "image/webp");
     asyncCreator->scheduleAsyncBlobCreation(useIdlePeriodScheduling, quality);
 }
 
 void HTMLCanvasElement::addListener(CanvasDrawListener* listener)
 {
     m_listeners.add(listener);
 }
 
@@ skipping 480 matching lines @@
         return m_context->getIdFromControl(element);
     return String();
 }
 
 void HTMLCanvasElement::createSurfaceLayerBridge()
 {
     m_surfaceLayerBridge = wrapUnique(new CanvasSurfaceLayerBridge());
 }
 
 } // namespace blink