Remove unnecessary CanvasAsyncBlobCreator keep alive protection.

third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp

Index: third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp
diff --git a/third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp b/third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp
index 7cf1fdaf454d2dc6744af55e75924bde384aa464..6d7c97bc792f6226a2281c4ed28272348fc48765 100644
--- a/third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp
+++ b/third_party/WebKit/Source/core/html/canvas/CanvasAsyncBlobCreator.cpp
@@ -2,12 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "CanvasAsyncBlobCreator.h"
+#include "core/html/canvas/CanvasAsyncBlobCreator.h"
 
 #include "core/fileapi/Blob.h"
 #include "platform/ThreadSafeFunctional.h"
 #include "platform/graphics/ImageBuffer.h"
-#include "platform/heap/Handle.h"
 #include "platform/image-encoders/skia/JPEGImageEncoder.h"
 #include "platform/image-encoders/skia/PNGImageEncoder.h"
 #include "platform/threading/BackgroundTaskRunner.h"
@@ -60,9 +59,6 @@ void CanvasAsyncBlobCreator::scheduleAsyncBlobCreation(bool canUseIdlePeriodSche
     // TODO: async blob creation should be supported in worker_pool threads as well. but right now blink does not have that
     ASSERT(isMainThread());
 
-    // Make self-reference to keep this object alive until the final task completes
-    m_keepAlive = this;
-
     // At the time being, progressive encoding is only applicable to png image format,
     // and thus idle tasks scheduling can only be applied to png image format.
     // TODO(xlai): Progressive encoding on jpeg and webp image formats (crbug.com/571398, crbug.com/571399)
@@ -82,7 +78,6 @@ void CanvasAsyncBlobCreator::initiateJpegEncoding(const double& quality)
     m_jpegEncoderState = JPEGImageEncoderState::create(m_size, quality, m_encodedImage.get());
     if (!m_jpegEncoderState) {
         Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&BlobCallback::handleEvent, m_callback, nullptr));
-        m_keepAlive.clear();
         return;
     }
     BackgroundTaskRunner::TaskSize taskSize = (m_size.height() * m_size.width() >= LongTaskImageSizeThreshold) ? BackgroundTaskRunner::TaskSizeLongRunningTask : BackgroundTaskRunner::TaskSizeShortRunningTask;
@@ -95,7 +90,6 @@ void CanvasAsyncBlobCreator::initiatePngEncoding(double deadlineSeconds)
     m_pngEncoderState = PNGImageEncoderState::create(m_size, m_encodedImage.get());
     if (!m_pngEncoderState) {
         Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&BlobCallback::handleEvent, m_callback, nullptr));
-        m_keepAlive.clear();
         return;
     }
 
@@ -124,11 +118,10 @@ void CanvasAsyncBlobCreator::idleEncodeRowsPng(double deadlineSeconds)
     m_numRowsCompleted = m_size.height();
     PNGImageEncoder::finalizePng(m_pngEncoderState.get());
 
-    if (isDeadlineNearOrPassed(deadlineSeconds)) {
+    if (isDeadlineNearOrPassed(deadlineSeconds))
         Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&CanvasAsyncBlobCreator::createBlobAndCall, this));
-    } else {
+    else
         this->createBlobAndCall();
-    }
 }
 
 void CanvasAsyncBlobCreator::createBlobAndCall()
@@ -136,7 +129,6 @@ void CanvasAsyncBlobCreator::createBlobAndCall()
     ASSERT(isMainThread());
     Blob* resultBlob = Blob::create(m_encodedImage->data(), m_encodedImage->size(), m_mimeType);
     Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, bind(&BlobCallback::handleEvent, m_callback, resultBlob));
-    clearSelfReference(); // self-destruct once job is done.
 }
 
 void CanvasAsyncBlobCreator::encodeImageOnEncoderThread(double quality)
@@ -144,39 +136,17 @@ void CanvasAsyncBlobCreator::encodeImageOnEncoderThread(double quality)
     ASSERT(!isMainThread());
 
     bool success;
-    if (m_mimeType == "image/jpeg") {
+    if (m_mimeType == "image/jpeg")
         success = JPEGImageEncoder::encodeWithPreInitializedState(m_jpegEncoderState.release(), m_data->data());
-    } else {
+    else
         success = ImageDataBuffer(m_size, m_data->data()).encodeImage(m_mimeType, quality, m_encodedImage.get());
-    }
 
     if (!success) {
-        scheduleCreateNullptrAndCallOnMainThread();
+        Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, threadSafeBind(&BlobCallback::handleEvent, m_callback.get(), nullptr));
         return;
     }
 
-    scheduleCreateBlobAndCallOnMainThread();
-}
-
-void CanvasAsyncBlobCreator::clearSelfReference()
-{
-    // Some persistent members in CanvasAsyncBlobCreator can only be destroyed
-    // on the thread that creates them. In this case, it's the main thread.
-    ASSERT(isMainThread());
-    m_keepAlive.clear();
-}
-
-void CanvasAsyncBlobCreator::scheduleCreateBlobAndCallOnMainThread()
-{
-    ASSERT(!isMainThread());
     Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, threadSafeBind(&CanvasAsyncBlobCreator::createBlobAndCall, AllowCrossThreadAccess(this)));
 }
 
-void CanvasAsyncBlobCreator::scheduleCreateNullptrAndCallOnMainThread()
-{
-    ASSERT(!isMainThread());
-    Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, threadSafeBind(&BlobCallback::handleEvent, m_callback.get(), nullptr));
-    Platform::current()->mainThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, threadSafeBind(&CanvasAsyncBlobCreator::clearSelfReference, AllowCrossThreadAccess(this)));
-}
-
 } // namespace blink