Don't try to render composited selection in throttled frame

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 "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/frame/FrameView.h"
 #include "core/html/HTMLIFrameElement.h"
+#include "core/page/FocusController.h"
+#include "core/page/Page.h"
 #include "platform/testing/URLTestHelpers.h"
 #include "platform/testing/UnitTestHelpers.h"
 #include "public/web/WebHitTestResult.h"
 #include "public/web/WebSettings.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebRemoteFrameImpl.h"
 #include "web/tests/sim/SimCompositor.h"
 #include "web/tests/sim/SimDisplayItemList.h"
 #include "web/tests/sim/SimRequest.h"
@@ skipping 324 matching lines @@
     webView().mainFrameImpl()->frameView()->setScrollPosition(DoublePoint(0, 480), ProgrammaticScroll);
     auto displayItems = compositeFrame();
     EXPECT_FALSE(displayItems.contains(SimCanvas::Rect, "red"));
     EXPECT_FALSE(displayItems.contains(SimCanvas::Rect, "green"));
 
     // Make sure the new style shows up instead of the old one.
     auto displayItems2 = compositeFrame();
     EXPECT_TRUE(displayItems2.contains(SimCanvas::Rect, "green"));
 }
 
+TEST_F(FrameThrottlingTest, ThrottledFrameWithFocus)
+{
+    webView().settings()->setJavaScriptEnabled(true);
+    webView().settings()->setAcceleratedCompositingEnabled(true);
+    RuntimeEnabledFeatures::setCompositedSelectionUpdateEnabled(true);
+
+    // Create a hidden frame which is throttled and has a text selection.
+    SimRequest mainResource("https://example.com/", "text/html");
+    SimRequest frameResource("https://example.com/iframe.html", "text/html");
+
+    loadURL("https://example.com/");
+    mainResource.complete("<iframe id=frame sandbox=allow-scripts src=iframe.html></iframe>");
+    frameResource.complete(
+        "some text to select\n"
+        "<script>\n"
+        "var range = document.createRange();\n"
+        "range.selectNode(document.body);\n"
+        "window.getSelection().addRange(range);\n"
+        "</script>\n");
+
+    // Move the frame offscreen to throttle it.
+    auto* frameElement = toHTMLIFrameElement(document().getElementById("frame"));
+    frameElement->setAttribute(styleAttr, "transform: translateY(480px)");
+    EXPECT_FALSE(frameElement->contentDocument()->view()->canThrottleRendering());
+    compositeFrame();
+    EXPECT_TRUE(frameElement->contentDocument()->view()->canThrottleRendering());
+
+    // Give the frame focus and do another composite. The selection in the
+    // compositor should be cleared because the frame is throttled.
+    EXPECT_FALSE(compositor().hasSelection());
+    document().page()->focusController().setFocusedFrame(frameElement->contentDocument()->frame());
+    document().body()->setAttribute(styleAttr, "background: green");
+    compositeFrame();
+    EXPECT_FALSE(compositor().hasSelection());
+}
+
 TEST(RemoteFrameThrottlingTest, ThrottledLocalRoot)
 {
     FrameTestHelpers::TestWebViewClient viewClient;
     WebViewImpl* webView = WebViewImpl::create(&viewClient);
     webView->resize(WebSize(640, 480));
 
     // Create a remote root frame with a local child frame.
     FrameTestHelpers::TestWebRemoteFrameClient remoteClient;
     webView->setMainFrame(remoteClient.frame());
     remoteClient.frame()->setReplicatedOrigin(WebSecurityOrigin::createUnique());
@@ skipping 70 matching lines @@
 
     // Scroll down to unthrottle the frame.
     webView().mainFrameImpl()->frameView()->setScrollPosition(DoublePoint(0, 480), ProgrammaticScroll);
     document().view()->updateAllLifecyclePhases();
     testing::runPendingTasks();
     // The fixed background in the throttled sub frame should be considered.
     EXPECT_TRUE(document().view()->shouldScrollOnMainThread());
 }
 
 } // namespace blink