Improve robustness of lost context checks in Canvas2DLayerBridge

third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp

 /*
  * Copyright (C) 2012 Google Inc. 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.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 183 matching lines @@
 {
     // Need to flush skia's internal queue because texture is about to be accessed directly
     GrContext* grContext = m_contextProvider->grContext();
     grContext->flush();
 
     ImageInfo imageInfo = createIOSurfaceBackedTexture();
     if (imageInfo.empty())
         return false;
 
     gpu::gles2::GLES2Interface* gl = contextGL();
+    if (!gl)
+        return false;
+
     GLuint imageTexture = skia::GrBackendObjectToGrGLTextureInfo(image->getTextureHandle(true))->fID;
     gl->CopySubTextureCHROMIUM(imageTexture, imageInfo.m_textureId, 0, 0, 0, 0, m_size.width(), m_size.height(), GL_FALSE, GL_FALSE, GL_FALSE);
 
     MailboxInfo& info = m_mailboxes.first();
     info.m_mailbox.textureTarget = GC3D_TEXTURE_RECTANGLE_ARB;
     gl->GenMailboxCHROMIUM(info.m_mailbox.name);
     gl->ProduceTextureDirectCHROMIUM(imageInfo.m_textureId, info.m_mailbox.textureTarget, info.m_mailbox.name);
     info.m_mailbox.allowOverlay = true;
 
     const GLuint64 fenceSync = gl->InsertFenceSyncCHROMIUM();
@@ skipping 15 matching lines @@
 
 Canvas2DLayerBridge::ImageInfo Canvas2DLayerBridge::createIOSurfaceBackedTexture()
 {
     if (!m_imageInfoCache.isEmpty()) {
         Canvas2DLayerBridge::ImageInfo info = m_imageInfoCache.last();
         m_imageInfoCache.removeLast();
         return info;
     }
 
     gpu::gles2::GLES2Interface* gl = contextGL();
+    if (!gl)
+        return Canvas2DLayerBridge::ImageInfo();
+
     GLuint imageId = gl->CreateGpuMemoryBufferImageCHROMIUM(m_size.width(), m_size.height(), GL_RGBA, GC3D_SCANOUT_CHROMIUM);
     if (!imageId)
         return Canvas2DLayerBridge::ImageInfo();
 
     GLuint textureId;
     gl->GenTextures(1, &textureId);
     GLenum target = GC3D_TEXTURE_RECTANGLE_ARB;
     gl->BindTexture(target, textureId);
     gl->TexParameteri(target, GL_TEXTURE_MAG_FILTER, getGLFilter());
     gl->TexParameteri(target, GL_TEXTURE_MIN_FILTER, getGLFilter());
     gl->TexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     gl->TexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     gl->BindTexImage2DCHROMIUM(target, imageId);
 
     return Canvas2DLayerBridge::ImageInfo(imageId, textureId);
 }
 
 void Canvas2DLayerBridge::deleteCHROMIUMImage(ImageInfo info)
 {
     gpu::gles2::GLES2Interface* gl = contextGL();
-    if (gl->GetGraphicsResetStatusKHR() != GL_NO_ERROR)
+    if (!gl)
         return;
 
     GLenum target = GC3D_TEXTURE_RECTANGLE_ARB;
     gl->BindTexture(target, info.m_textureId);
     gl->ReleaseTexImage2DCHROMIUM(target, info.m_imageId);
     gl->DestroyImageCHROMIUM(info.m_imageId);
     gl->DeleteTextures(1, &info.m_textureId);
     gl->BindTexture(target, 0);
 
     resetSkiaTextureBinding();
@@ skipping 45 matching lines @@
     // Need to flush skia's internal queue because texture is about to be accessed directly
     grContext->flush();
 
     // Because of texture sharing with the compositor, we must invalidate
     // the state cached in skia so that the deferred copy on write
     // in SkSurface_Gpu does not make any false assumptions.
     mailboxInfo.m_image->getTexture()->textureParamsModified();
     mailboxInfo.m_mailbox.textureTarget = GL_TEXTURE_2D;
 
     gpu::gles2::GLES2Interface* gl = contextGL();
+    if (!gl)
+        return false;
+
     GLuint textureID = skia::GrBackendObjectToGrGLTextureInfo(mailboxInfo.m_image->getTextureHandle(true))->fID;
     gl->BindTexture(GL_TEXTURE_2D, textureID);
     gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, getGLFilter());
     gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, getGLFilter());
     gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 
     // Re-use the texture's existing mailbox, if there is one.
     if (mailboxInfo.m_image->getTexture()->getCustomData()) {
         ASSERT(mailboxInfo.m_image->getTexture()->getCustomData()->size() == sizeof(mailboxInfo.m_mailbox.name));
@@ skipping 352 matching lines @@
     if (isAccelerated() && gl)
         gl->Flush();
 }
 
 
 gpu::gles2::GLES2Interface* Canvas2DLayerBridge::contextGL()
 {
     // Check on m_layer is necessary because contextGL() may be called during
     // the destruction of m_layer
     if (m_layer && !m_destructionInProgress) {
-        // Ensure rate limiter is disabled if context is lost.
-        checkSurfaceValid();
+        // Call checkSurfaceValid to ensure rate limiter is disabled if context is lost.
+        if (!checkSurfaceValid())
+            return nullptr;
     }
     return m_contextProvider ? m_contextProvider->contextGL() : nullptr;
 }
 
 bool Canvas2DLayerBridge::checkSurfaceValid()
 {
     ASSERT(!m_destructionInProgress);
     if (m_destructionInProgress)
         return false;
     if (isHibernating())
@@ skipping 264 matching lines @@
 #endif // USE_IOSURFACE_FOR_2D_CANVAS
 }
 
 void Canvas2DLayerBridge::Logger::reportHibernationEvent(HibernationEvent event)
 {
     DEFINE_STATIC_LOCAL(EnumerationHistogram, hibernationHistogram, ("Canvas.HibernationEvents", HibernationEventCount));
     hibernationHistogram.count(event);
 }
 
 } // namespace blink