Invalidate m_image after GPU-GPU texture copy

third_party/WebKit/Source/platform/graphics/StaticBitmapImage.cpp

 // Copyright 2014 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 "platform/graphics/StaticBitmapImage.h"
 
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/ImageObserver.h"
 #include "public/platform/Platform.h"
@@ skipping 86 matching lines @@
     backendTexture.fHeight = m_mailbox.textureSize.height;
     backendTexture.fConfig = kSkia8888_GrPixelConfig;
     backendTexture.fTextureHandle = skia::GrGLTextureInfoToGrBackendObject(textureInfo);
     sk_sp<SkImage> skImage = SkImage::MakeFromAdoptedTexture(grContext, backendTexture);
     m_image = fromSkSp(skImage);
     return textureId;
 }
 
 void StaticBitmapImage::copyToTexture(WebGraphicsContext3DProvider* provider, GLuint destinationTexture, GLenum internalFormat, GLenum destType, bool flipY)
 {
-    GLuint textureId = textureIdForWebGL(provider);
+    GLuint textureId = switchStorageToSkImageForWebGL(provider);
     gpu::gles2::GLES2Interface* gl = provider->contextGL();
     if (!gl)
         return;
     gl->CopyTextureCHROMIUM(textureId, destinationTexture, internalFormat, destType, flipY, false, false);
     const GLuint64 fenceSync = gl->InsertFenceSyncCHROMIUM();
     gl->Flush();
     GLbyte syncToken[24];
     gl->GenSyncTokenCHROMIUM(fenceSync, syncToken);
+    // Get a new mailbox because we cannot retain a texture in the WebGL context.
+    switchStorageToMailbox(provider);
 }
 
 bool StaticBitmapImage::switchStorageToMailbox(WebGraphicsContext3DProvider* provider)
 {
     m_mailbox.textureSize = WebSize(m_image->width(), m_image->height());
     GrContext* grContext = provider->grContext();
     if (!grContext)
         return false;
     grContext->flush();
     m_mailbox.textureTarget = GL_TEXTURE_2D;
     gpu::gles2::GLES2Interface* gl = provider->contextGL();
     if (!gl)
         return false;
     GLuint textureID = skia::GrBackendObjectToGrGLTextureInfo(m_image->getTextureHandle(true))->fID;
     gl->BindTexture(GL_TEXTURE_2D, textureID);
 
     gl->GenMailboxCHROMIUM(m_mailbox.name);
     gl->ProduceTextureCHROMIUM(GL_TEXTURE_2D, m_mailbox.name);
     const GLuint64 fenceSync = gl->InsertFenceSyncCHROMIUM();
     gl->Flush();
     gl->GenSyncTokenCHROMIUM(fenceSync, m_mailbox.syncToken);
     m_mailbox.validSyncToken = true;
     gl->BindTexture(GL_TEXTURE_2D, 0);
     grContext->resetContext(kTextureBinding_GrGLBackendState);
+    m_image = nullptr;
     return true;
 }
 
 // This function is called only in the case that m_image is texture backed.
-GLuint StaticBitmapImage::textureIdForWebGL(WebGraphicsContext3DProvider* contextProvider)
+GLuint StaticBitmapImage::switchStorageToSkImageForWebGL(WebGraphicsContext3DProvider* contextProvider)
 {
     DCHECK(!m_image || m_image->isTextureBacked());
     GLuint textureId = 0;
     if (m_image) {
         // SkImage is texture-backed on the shared context
         if (!hasMailbox()) {
             std::unique_ptr<WebGraphicsContext3DProvider> sharedProvider = wrapUnique(Platform::current()->createSharedOffscreenGraphicsContext3DProvider());
             if (!switchStorageToMailbox(sharedProvider.get()))
                 return 0;
             textureId = switchStorageToSkImage(contextProvider);
-            // Get a new mailbox because we cannot retain a texture in the WebGL context.
-            if (!switchStorageToMailbox(contextProvider))
-                return 0;
             return textureId;
         }
     }
     DCHECK(hasMailbox());
     textureId = switchStorageToSkImage(contextProvider);
-    if (!switchStorageToMailbox(contextProvider))
-        return 0;
     return textureId;
 }
 
 PassRefPtr<SkImage> StaticBitmapImage::imageForCurrentFrame()
 {
     if (m_image)
         return m_image;
     // No mailbox, return null;
     if (!hasMailbox())
         return nullptr;
     // Has mailbox, consume mailbox, prepare a new mailbox if contextProvider is not null (3D).
     DCHECK(isMainThread());
     // TODO(xidachen): make this work on a worker thread.
     std::unique_ptr<WebGraphicsContext3DProvider> sharedProvider = wrapUnique(Platform::current()->createSharedOffscreenGraphicsContext3DProvider());
     if (!switchStorageToSkImage(sharedProvider.get()))
         return nullptr;
     return m_image;
 }
 
 } // namespace blink