Make browser hit testing return correct SurfaceId with nested Surfaces

content/browser/site_per_process_browsertest.cc

Index: content/browser/site_per_process_browsertest.cc
diff --git a/content/browser/site_per_process_browsertest.cc b/content/browser/site_per_process_browsertest.cc
index c91e6b1592c5ed9150be7eb3b562882b55a28d60..24fb1e9248866b169861a12aafb4d0d33804925c 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -740,6 +740,82 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessHighDPIBrowserTest,
   SurfaceHitTestTestHelper(shell(), embedded_test_server());
 }
 
+// Test that mouse events are being routed to the correct RenderWidgetHostView
+// when there are nested out-of-process iframes.
+#if defined(OS_ANDROID)
+// Browser process hit testing is not implemented on Android.
+// https://crbug.com/491334
+#define MAYBE_NestedSurfaceHitTestTest DISABLED_NestedSurfaceHitTestTest
+#else
+#define MAYBE_NestedSurfaceHitTestTest NestedSurfaceHitTestTest
+#endif
+IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest,
+                       MAYBE_NestedSurfaceHitTestTest) {
+  GURL main_url(embedded_test_server()->GetURL(
+      "/frame_tree/page_with_positioned_nested_frames.html"));
+  NavigateToURL(shell(), main_url);
+
+  // It is safe to obtain the root frame tree node here, as it doesn't change.
+  FrameTreeNode* root = static_cast<WebContentsImpl*>(shell()->web_contents())
+                            ->GetFrameTree()
+                            ->root();
+  ASSERT_EQ(1U, root->child_count());
+
+  FrameTreeNode* parent_iframe_node = root->child_at(0);
+  GURL site_url(embedded_test_server()->GetURL(
+      "a.com", "/frame_tree/page_with_positioned_frame.html"));
+  EXPECT_EQ(site_url, parent_iframe_node->current_url());
+  EXPECT_NE(shell()->web_contents()->GetSiteInstance(),
+            parent_iframe_node->current_frame_host()->GetSiteInstance());
+
+  FrameTreeNode* nested_iframe_node = parent_iframe_node->child_at(0);
+  GURL nested_site_url(
+      embedded_test_server()->GetURL("baz.com", "/title1.html"));
+  EXPECT_EQ(nested_site_url, nested_iframe_node->current_url());
+  EXPECT_NE(shell()->web_contents()->GetSiteInstance(),
+            nested_iframe_node->current_frame_host()->GetSiteInstance());
+  EXPECT_NE(parent_iframe_node->current_frame_host()->GetSiteInstance(),
+            nested_iframe_node->current_frame_host()->GetSiteInstance());
+
+  // Create listeners for mouse events.
+  RenderWidgetHostMouseEventMonitor main_frame_monitor(
+      root->current_frame_host()->GetRenderWidgetHost());
+  RenderWidgetHostMouseEventMonitor nested_frame_monitor(
+      nested_iframe_node->current_frame_host()->GetRenderWidgetHost());
+
+  RenderWidgetHostInputEventRouter* router =
+      static_cast<WebContentsImpl*>(shell()->web_contents())
+          ->GetInputEventRouter();
+
+  RenderWidgetHostViewBase* root_view = static_cast<RenderWidgetHostViewBase*>(
+      root->current_frame_host()->GetRenderWidgetHost()->GetView());
+  RenderWidgetHostViewBase* rwhv_nested =
+      static_cast<RenderWidgetHostViewBase*>(
+          nested_iframe_node->current_frame_host()
+              ->GetRenderWidgetHost()
+              ->GetView());
+
+  SurfaceHitTestReadyNotifier notifier(
+      static_cast<RenderWidgetHostViewChildFrame*>(rwhv_nested));
+  notifier.WaitForSurfaceReady();
+
+  // Target input event to nested frame.
+  blink::WebMouseEvent nested_event;
+  nested_event.type = blink::WebInputEvent::MouseDown;
+  nested_event.button = blink::WebPointerProperties::ButtonLeft;
+  nested_event.x = 125;
+  nested_event.y = 125;
+  nested_event.clickCount = 1;
+  nested_frame_monitor.ResetEventReceived();
+  main_frame_monitor.ResetEventReceived();
+  router->RouteMouseEvent(root_view, &nested_event);
+
+  EXPECT_TRUE(nested_frame_monitor.EventWasReceived());
+  EXPECT_EQ(21, nested_frame_monitor.event().x);
+  EXPECT_EQ(21, nested_frame_monitor.event().y);
+  EXPECT_FALSE(main_frame_monitor.EventWasReceived());
+}
+
 // This test tests that browser process hittesting ignores frames with
 // pointer-events: none.
 #if defined(OS_ANDROID)