[blink] Request compositing update when canvas hibernates/wakes up.

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

+// Copyright 2017 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 "core/html/HTMLCanvasElement.h"
+
+#include "core/dom/Document.h"
+#include "core/frame/FrameView.h"
+#include "core/frame/Settings.h"
+#include "core/html/canvas/CanvasContextCreationAttributes.h"
+#include "core/layout/LayoutBoxModelObject.h"
+#include "core/page/Page.h"
+#include "core/paint/PaintLayer.h"
+#include "core/testing/DummyPageHolder.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class HTMLCanvasElementTest : public testing::Test {
+ protected:
+  HTMLCanvasElementTest() {}
+
+  void SetUp() override;
+
+  Document& document() const { return *m_document; }
+
+  void setHtmlInnerHTML(const char* htmlContent);
+
+  void createContext(HTMLCanvasElement*, OpacityMode);
+
+  std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
+  Persistent<Document> m_document;
+};
+
+void OverrideSettings(Settings& settings) {
+  // Simulate that we allow scripts, so that HTMLCanvasElement uses
+  // LayoutHTMLCanvas.
+  settings.setScriptEnabled(true);
+}
+
+void HTMLCanvasElementTest::SetUp() {
+  m_dummyPageHolder = DummyPageHolder::create(
+      IntSize(800, 600), nullptr, nullptr, &OverrideSettings, nullptr);
+  m_document = &m_dummyPageHolder->document();
+  DCHECK(m_document);
+}
+
+void HTMLCanvasElementTest::setHtmlInnerHTML(const char* htmlContent) {
+  document().documentElement()->setInnerHTML(String::fromUTF8(htmlContent));
+  document().view()->updateAllLifecyclePhases();
+}
+
+void HTMLCanvasElementTest::createContext(HTMLCanvasElement* canvas,
+                                          OpacityMode opacityMode) {
+  String canvasType("2d");
+  CanvasContextCreationAttributes attributes;
+  attributes.setAlpha(opacityMode == NonOpaque);
+  canvas->getCanvasRenderingContext(canvasType, attributes);
+}
+
+// https://crbug.com/708445: When visibility changes, the compositing reasons
+// for the canvas element may change. Thus, it should request a compositing
+// update.
+TEST_F(HTMLCanvasElementTest, RequestsCompositingUpdateWhenVisibilityChanges) {
+  setHtmlInnerHTML("<canvas id='canvas' width='800' height='600'></canvas>");
+  document().view()->layout();
+
+  auto* element = document().getElementById("canvas");
+  ASSERT_TRUE(element);
+  ASSERT_TRUE(isHTMLCanvasElement(element));
+  HTMLCanvasElement* canvas = toHTMLCanvasElement(element);
+  EXPECT_TRUE(canvas->layoutBoxModelObject());
+  PaintLayer* layer = canvas->layoutBoxModelObject()->layer();
+  EXPECT_TRUE(layer);
+
+  // Create context so that pageVisibilityChanged() doesn't early-out.
+  createContext(canvas, NonOpaque);
+  document().view()->updateAllLifecyclePhases();
+
+  document().page()->setVisibilityState(PageVisibilityStateHidden, false);
+  EXPECT_TRUE(layer->needsCompositingInputsUpdate());
+  document().view()->updateAllLifecyclePhases();
+
+  document().page()->setVisibilityState(PageVisibilityStateVisible, false);
+  EXPECT_TRUE(layer->needsCompositingInputsUpdate());
+}
+
+}  // namespace blink