Android: Don't destroy LayerTreeHost when Surface goes away

chrome/browser/android/thumbnail/thumbnail.cc

 // 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 "base/bind.h"
+#include "base/location.h"
 #include "base/logging.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/browser/android/thumbnail/thumbnail.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "ui/android/resources/ui_resource_provider.h"
 #include "ui/gfx/geometry/size_conversions.h"
 
 namespace {
 
 SkBitmap CreateSmallHolderBitmap() {
   SkBitmap small_bitmap;
@@ skipping 22 matching lines @@
                      float scale,
                      ui::UIResourceProvider* ui_resource_provider,
                      ThumbnailDelegate* thumbnail_delegate)
     : tab_id_(tab_id),
       time_stamp_(time_stamp),
       scale_(scale),
       bitmap_(gfx::Size(1, 1), true),
       ui_resource_id_(0),
       retrieved_(false),
       ui_resource_provider_(ui_resource_provider),
-      thumbnail_delegate_(thumbnail_delegate) {
+      thumbnail_delegate_(thumbnail_delegate),
+      weak_factory_(this) {
 }
 
 Thumbnail::~Thumbnail() {
   ClearUIResourceId();
 }
 
 void Thumbnail::SetBitmap(const SkBitmap& bitmap) {
   DCHECK(!bitmap.empty());
   retrieved_ = false;
   ClearUIResourceId();
@@ skipping 17 matching lines @@
 }
 
 void Thumbnail::CreateUIResource() {
   DCHECK(ui_resource_provider_);
   if (!ui_resource_id_)
     ui_resource_id_ = ui_resource_provider_->CreateUIResource(this);
 }
 
 cc::UIResourceBitmap Thumbnail::GetBitmap(cc::UIResourceId uid,
                                           bool resource_lost) {
-  if (retrieved_)
+  if (retrieved_) {
+    // InvalidateCachedThumbnail() causes |this| to be deleted, so
+    // don't delete the resource while LayerTeeHost calls into |this|
+    // to avoid reentry there.
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(&Thumbnail::DoInvalidate, weak_factory_.GetWeakPtr()));
     return bitmap_;
+  }
 
   retrieved_ = true;
 
   cc::UIResourceBitmap old_bitmap(bitmap_);
   // Return a place holder for all other calls to GetBitmap.
   bitmap_ = cc::UIResourceBitmap(CreateSmallHolderBitmap());
   return old_bitmap;
 }
 
-void Thumbnail::UIResourceIsInvalid() {
-  ui_resource_id_ = 0;
+void Thumbnail::DoInvalidate() {
   if (thumbnail_delegate_)
     thumbnail_delegate_->InvalidateCachedThumbnail(this);
 }
 
 void Thumbnail::ClearUIResourceId() {
   if (ui_resource_id_ && ui_resource_provider_)
     ui_resource_provider_->DeleteUIResource(ui_resource_id_);
   ui_resource_id_ = 0;
 }