Throttle rendering pipeline for invisible frames

third_party/WebKit/Source/web/tests/FrameThrottlingTest.cpp

+// Copyright 2015 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 "config.h"
+
+#include "core/dom/Document.h"
+#include "core/frame/FrameView.h"
+#include "platform/testing/UnitTestHelpers.h"
+#include "public/web/WebElement.h"
+#include "public/web/WebHitTestResult.h"
+#include "web/WebLocalFrameImpl.h"
+#include "web/tests/FrameTestHelpers.h"
+#include "web/tests/sim/SimCompositor.h"
+#include "web/tests/sim/SimDisplayItemList.h"
+#include "web/tests/sim/SimLayerTreeView.h"
+#include "web/tests/sim/SimNetwork.h"
+#include "web/tests/sim/SimRequest.h"
+#include "web/tests/sim/SimWebViewClient.h"
+#include <gtest/gtest.h>
+
+namespace blink {
+
+class FrameThrottlingTest : public ::testing::Test {
+protected:
+    FrameThrottlingTest()
+        : m_webViewClient(m_layerTreeView)
+        , m_compositor(m_layerTreeView)
+    {
+        m_webViewHelper.initialize(true, &m_webFrameClient, &m_webViewClient);
+        m_compositor.setWebViewImpl(webView());
+        m_layerTreeView.setDeferCommits(false);
+        webView().resize(WebSize(640, 480));
+    }
+
+    ~FrameThrottlingTest() override { }
+
+    void loadURL(const String& url)
+    {
+        WebURLRequest request;
+        request.initialize();
+        request.setURL(KURL(ParsedURLString, url));
+        webView().mainFrameImpl()->loadRequest(request);
+    }
+
+    void loadHTML(const String& html)
+    {
+        SimRequest mainResource("https://example.com/test.html", "text/html");
+        loadURL("https://example.com/test.html");
+        mainResource.start();
+        mainResource.write(html);
+        mainResource.finish();
+        m_webFrameClient.waitForLoadToComplete();
+        webView().layout();
+    }
+
+    WebElement setupPageWithThrottleableFrame()
+    {
+        loadHTML("<iframe sandbox id=frame></iframe>");
+        WebExceptionCode ec;
+        WebElement frameElement = root().querySelector("#frame", ec);
+        EXPECT_EQ(0, ec);
+        return frameElement;
+    }
+
+    Document& document()
+    {
+        return *webView().mainFrameImpl()->frame()->document();
+    }
+
+    WebNode root()
+    {
+        return WebNode(document().documentElement());
+    }
+
+    WebViewImpl& webView()
+    {
+        return *m_webViewHelper.webViewImpl();
+    }
+
+    SimDisplayItemList compositeFrame()
+    {
+        SimDisplayItemList displayItems = m_compositor.beginFrame();
+        // Ensure intersection observer notifications get delivered.
+        testing::runPendingTasks();
+        return displayItems;
+    }
+
+    SimNetwork m_network;
+    SimLayerTreeView m_layerTreeView;
+    SimWebViewClient m_webViewClient;
+    SimCompositor m_compositor;
+    FrameTestHelpers::TestWebFrameClient m_webFrameClient;
+    FrameTestHelpers::WebViewHelper m_webViewHelper;
+};
+
+TEST_F(FrameThrottlingTest, throttleInvisibleFrames)
+{
+    WebElement frameElement = setupPageWithThrottleableFrame();
+
+    // Initially both frames are visible.
+    FrameView* frameView = document().view();
+    FrameView* childFrameView = toLocalFrame(frameView->frame().tree().firstChild())->view();
+    EXPECT_FALSE(frameView->isHiddenForThrottling());
+    EXPECT_FALSE(childFrameView->isHiddenForThrottling());
+
+    // Moving the child fully outside the parent makes it invisible.
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_FALSE(frameView->isHiddenForThrottling());
+    EXPECT_TRUE(childFrameView->isHiddenForThrottling());
+
+    // A partially visible child is considered visible.
+    frameElement.setAttribute("style", "transform: translate(-50px, 0px, 0px)");
+    compositeFrame();
+    EXPECT_FALSE(frameView->isHiddenForThrottling());
+    EXPECT_FALSE(childFrameView->isHiddenForThrottling());
+}
+
+TEST_F(FrameThrottlingTest, viewportVisibilityFullyClipped)
+{
+    setupPageWithThrottleableFrame();
+
+    // A child which is fully clipped away by its ancestor should become invisible.
+    FrameView* frameView = document().view();
+    FrameView* childFrameView = toLocalFrame(frameView->frame().tree().firstChild())->view();
+    webView().resize(WebSize(0, 0));
+    compositeFrame();
+    EXPECT_TRUE(frameView->isHiddenForThrottling());
+    EXPECT_TRUE(childFrameView->isHiddenForThrottling());
+}
+
+TEST_F(FrameThrottlingTest, hiddenSameOriginFramesAreNotThrottled)
+{
+    // Create a document with doubly nested iframes.
+    loadHTML("<iframe id=frame srcdoc='<iframe></iframe>'></iframe>");
+    WebExceptionCode ec;
+    WebElement frameElement = root().querySelector("#frame", ec);
+    EXPECT_EQ(0, ec);
+
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+    LocalFrame* grandChildFrame = toLocalFrame(childFrame->tree().firstChild());
+    FrameView* childFrameView = childFrame->view();
+    FrameView* grandChildFrameView = grandChildFrame->view();
+    EXPECT_FALSE(frameView->canThrottleRendering());
+    EXPECT_FALSE(childFrameView->canThrottleRendering());
+    EXPECT_FALSE(grandChildFrameView->canThrottleRendering());
+
+    // Hidden same origin frames are not throttled.
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_FALSE(frameView->canThrottleRendering());
+    EXPECT_FALSE(childFrameView->canThrottleRendering());
+    EXPECT_FALSE(grandChildFrameView->canThrottleRendering());
+}
+
+TEST_F(FrameThrottlingTest, hiddenCrossOriginFramesAreThrottled)
+{
+    // Create a document with doubly nested iframes.
+    loadHTML("<iframe id=frame srcdoc='<iframe sandbox></iframe>'></iframe>");
+    WebExceptionCode ec;
+    WebElement frameElement = root().querySelector("#frame", ec);
+    EXPECT_EQ(0, ec);
+
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+    LocalFrame* grandChildFrame = toLocalFrame(childFrame->tree().firstChild());
+    FrameView* childFrameView = childFrame->view();
+    FrameView* grandChildFrameView = grandChildFrame->view();
+    EXPECT_FALSE(frameView->canThrottleRendering());
+    EXPECT_FALSE(childFrameView->canThrottleRendering());
+    EXPECT_FALSE(grandChildFrameView->canThrottleRendering());
+
+    // Hidden cross origin frames are throttled.
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_FALSE(frameView->canThrottleRendering());
+    EXPECT_FALSE(childFrameView->canThrottleRendering());
+    EXPECT_TRUE(grandChildFrameView->canThrottleRendering());
+}
+
+TEST_F(FrameThrottlingTest, throttledLifecycleUpdate)
+{
+    WebElement frameElement = setupPageWithThrottleableFrame();
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+    FrameView* childFrameView = childFrame->view();
+
+    // Enable throttling for the child frame.
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_TRUE(childFrameView->canThrottleRendering());
+    EXPECT_EQ(DocumentLifecycle::PaintInvalidationClean, childFrame->document()->lifecycle().state());
+
+    // Mutating the throttled frame followed by a beginFrame will not result in
+    // a complete lifecycle update.
+    frameElement.setAttribute("width", "50");
+    compositeFrame();
+    EXPECT_EQ(DocumentLifecycle::StyleClean, childFrame->document()->lifecycle().state());
+
+    // A hit test will force a complete lifecycle update.
+    webView().hitTestResultAt(WebPoint(0, 0));
+    EXPECT_EQ(DocumentLifecycle::CompositingClean, childFrame->document()->lifecycle().state());
+}
+
+TEST_F(FrameThrottlingTest, unthrottlingFrameSchedulesAnimation)
+{
+    WebElement frameElement = setupPageWithThrottleableFrame();
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+    FrameView* childFrameView = childFrame->view();
+
+    // First make the child hidden to enable throttling.
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_TRUE(childFrameView->canThrottleRendering());
+    EXPECT_FALSE(m_layerTreeView.needsAnimate());
+
+    // Then bring it back on-screen. This should schedule an animation update.
+    frameElement.setAttribute("style", "");
+    compositeFrame();
+    EXPECT_TRUE(m_layerTreeView.needsAnimate());
+}
+
+TEST_F(FrameThrottlingTest, mutatingThrottledFrameDoesNotCauseAnimation)
+{
+    loadHTML("<iframe id=frame sandbox srcdoc='<style> html { background: red; } </style>'></iframe>");
+    WebExceptionCode ec;
+    WebElement frameElement = root().querySelector("#frame", ec);
+    EXPECT_EQ(0, ec);
+
+    // Check that the frame initially shows up.
+    m_layerTreeView.setDeferCommits(false);
+    SimDisplayItemList displayItems1 = compositeFrame();
+    EXPECT_TRUE(displayItems1.contains(SimCanvas::Rect, "red"));
+
+    // Move the frame offscreen to throttle it.
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+    EXPECT_TRUE(childFrame->view()->canThrottleRendering());
+
+    // Mutating the throttled frame should not cause an animation to be scheduled.
+    childFrame->document()->documentElement()->setInnerHTML("<style> html { background: green; } </style>", ASSERT_NO_EXCEPTION);
+    EXPECT_FALSE(m_layerTreeView.needsAnimate());
+
+    // Moving the frame back on screen to unthrottle it.
+    frameElement.setAttribute("style", "");
+    EXPECT_TRUE(m_layerTreeView.needsAnimate());
+
+    // The first frame we composite after unthrottling won't contain the
+    // frame's new contents because unthrottling happens at the end of the
+    // lifecycle update. We need to do another composite to refresh the frame's
+    // contents.
+    SimDisplayItemList displayItems2 = compositeFrame();
+    EXPECT_FALSE(displayItems2.contains(SimCanvas::Rect, "green"));
+    EXPECT_TRUE(m_layerTreeView.needsAnimate());
+
+    SimDisplayItemList displayItems3 = compositeFrame();
+    EXPECT_TRUE(displayItems3.contains(SimCanvas::Rect, "green"));
+}
+
+TEST_F(FrameThrottlingTest, synchronousLayoutInThrottledFrame)
+{
+    // Create a hidden frame which is throttled.
+    loadHTML("<iframe id=frame sandbox srcdoc='<div id=div></div>'></iframe>");
+    WebExceptionCode ec;
+    WebElement frameElement = root().querySelector("#frame", ec);
+    EXPECT_EQ(0, ec);
+    frameElement.setAttribute("style", "transform: translateY(480px)");
+    compositeFrame();
+
+    FrameView* frameView = document().view();
+    LocalFrame* childFrame = toLocalFrame(frameView->frame().tree().firstChild());
+
+    // Change the size of a div in the throttled frame.
+    Element* divElement = childFrame->document()->getElementById("div");
+    divElement->setAttribute(HTMLNames::styleAttr, "width: 50px");
+
+    // Querying the width of the div should do a synchronous layout update even
+    // though the frame is being throttled.
+    EXPECT_EQ(50, divElement->clientWidth());
+}
+
+} // namespace blink