content: fix GestureListenerManagerTest

This test is still mildly flaky. The issue is that while it waits
for a non-empty paint, this is not always enough. This makes the
test additionally wait for loading to complete and more importantly,
waits for a visual update. The latter is a good signal the renderer
will actually process events.

BUG=1091129
TEST=test only change

Change-Id: Iabc6d2dce83985086c56db916c8cc273e3ed65f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2303554Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#789280}

content/public/android/javatests/src/org/chromium/content/browser/GestureListenerManagerTest.java

@@ -21,6 +21,7 @@ import org.chromium.content_public.browser.GestureListenerManager;
 import org.chromium.content_public.browser.GestureStateListenerWithScroll;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.content_public.browser.WebContents;
+import org.chromium.content_public.browser.test.RenderFrameHostTestExt;
 import org.chromium.content_public.browser.test.util.TestCallbackHelperContainer;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
 import org.chromium.content_public.browser.test.util.TouchCommon;
@@ -90,10 +91,25 @@ public class GestureListenerManagerTest {
         // This needs to wait for first-paint, otherwise scrolling doesn't happen.
         TestCallbackHelperContainer callbackHelperContainer =
                 new TestCallbackHelperContainer(webContents);
-        CallbackHelper done = callbackHelperContainer.getOnFirstVisuallyNonEmptyPaintHelper();
         mActivityTestRule.loadUrl(webContents.getNavigationController(), callbackHelperContainer,
                 new LoadUrlParams(TEST_URL));
-        done.waitForCallback(0);
+        // Wait for both a paint and the page to finish loading. These may come in any order.
+        callbackHelperContainer.getOnFirstVisuallyNonEmptyPaintHelper().waitForCallback(0);
+        callbackHelperContainer.getOnPageFinishedHelper().waitForCallback(0);
+
+        // At this point the page has finished loading and a non-empty paint occurred. This does not
+        // mean the renderer is fully ready to process events (processing events requires layers,
+        // which may not have been created yet). Wait for a visual update, which should ensure the
+        // renderer is ready.
+        CallbackHelper callbackHelper = new CallbackHelper();
+        TestThreadUtils.runOnUiThreadBlocking(() -> {
+            new RenderFrameHostTestExt(webContents.getMainFrame())
+                    .updateVisualState((Boolean result) -> {
+                        Assert.assertTrue(result);
+                        callbackHelper.notifyCalled();
+                    });
+        });
+        callbackHelper.waitForFirst();
 
         final GestureStateListenerImpl listener = new GestureStateListenerImpl();
         TestThreadUtils.runOnUiThreadBlocking(() -> {

content/public/test/android/javatests/src/org/chromium/content_public/browser/test/RenderFrameHostTestExt.java

@@ -31,7 +31,13 @@ public class RenderFrameHostTestExt {
         nativeExecuteJavaScript(mNativeRenderFrameHostTestExt, script, callback);
     }
 
+    public void updateVisualState(Callback<Boolean> callback) {
+        nativeUpdateVisualState(mNativeRenderFrameHostTestExt, callback);
+    }
+
     private native long nativeInit(long renderFrameHostAndroidPtr);
     private native void nativeExecuteJavaScript(
             long nativeRenderFrameHostTestExt, String script, Callback<String> callback);
+    private native void nativeUpdateVisualState(
+            long nativeRenderFrameHostTestExt, Callback<Boolean> callback);
 }

content/public/test/android/render_frame_host_test_ext.cc

@@ -61,4 +61,14 @@ void RenderFrameHostTestExt::ExecuteJavaScript(
   render_frame_host_->ExecuteJavaScriptForTests(script, std::move(callback));
 }
 
+void RenderFrameHostTestExt::UpdateVisualState(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& obj,
+    const JavaParamRef<jobject>& jcallback) {
+  auto result_callback = base::BindOnce(
+      &base::android::RunBooleanCallbackAndroid,
+      base::android::ScopedJavaGlobalRef<jobject>(env, jcallback));
+  render_frame_host_->InsertVisualStateCallback(std::move(result_callback));
+}
+
 }  // namespace content

content/public/test/android/render_frame_host_test_ext.h

@@ -22,6 +22,11 @@ class RenderFrameHostTestExt : public base::SupportsUserData::Data {
                          const base::android::JavaParamRef<jobject>& obj,
                          const base::android::JavaParamRef<jstring>& jscript,
                          const base::android::JavaParamRef<jobject>& jcallback);
+  // This calls InsertVisualStateCallback(). See it for details on the return
+  // value.
+  void UpdateVisualState(JNIEnv* env,
+                         const base::android::JavaParamRef<jobject>& obj,
+                         const base::android::JavaParamRef<jobject>& jcallback);
 
  private:
   RenderFrameHostImpl* const render_frame_host_;