weblayer: fix bug where controls would show on rotation

onOffsetsChanged() does nothing if fullscreen. This changes the
code to call to setControlsOffset() so that the offsets are
correctly updated.

BUG=1149335
TEST=testTopViewRemainsHiddenOnFullscreenRotation

Change-Id: I419f629292caf5f4454a04920c6a9778c8f16731
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2575898
Reviewed-by: Robbie McElrath <rmcelrath@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#834026}

weblayer/browser/android/javatests/src/org/chromium/weblayer/test/FullscreenCallbackTest.java

@@ -7,13 +7,15 @@
 import androidx.test.filters.SmallTest;
 
 import org.junit.Assert;
-import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
+import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.DisabledTest;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
+import org.chromium.weblayer.Browser;
+import org.chromium.weblayer.BrowserControlsOffsetCallback;
 import org.chromium.weblayer.shell.InstrumentationActivity;
 
 /**
@@ -28,8 +30,8 @@ public class FullscreenCallbackTest {
     private InstrumentationActivity mActivity;
     private TestFullscreenCallback mDelegate;
 
-    @Before
-    public void setUp() {
+    // Launch WL and triggers html fullscreen.
+    private void enterFullscren() {
         String url = mActivityTestRule.getTestDataURL("fullscreen.html");
         mActivity = mActivityTestRule.launchShellWithUrl(url);
         Assert.assertNotNull(mActivity);
@@ -47,6 +49,7 @@ public void setUp() {
     @SmallTest
     @DisabledTest(message = "crbug.com/1133893")
     public void testFullscreen() {
+        enterFullscren();
         // Second touch exits.
         EventUtils.simulateTouchCenterOfView(mActivity.getWindow().getDecorView());
         mDelegate.waitForExitFullscreen();
@@ -56,6 +59,7 @@ public void testFullscreen() {
     @Test
     @SmallTest
     public void testExitFullscreenWhenDelegateCleared() {
+        enterFullscren();
         // Clearing the FullscreenCallback should exit fullscreen.
         TestThreadUtils.runOnUiThreadBlocking(
                 () -> { mActivity.getTab().setFullscreenCallback(null); });
@@ -66,6 +70,7 @@ public void testExitFullscreenWhenDelegateCleared() {
     @Test
     @SmallTest
     public void testExitFullscreenUsingRunnable() {
+        enterFullscren();
         // Running the runnable supplied to the delegate should exit fullscreen.
         TestThreadUtils.runOnUiThreadBlocking(mDelegate.mExitFullscreenRunnable);
         mDelegate.waitForExitFullscreen();
@@ -75,6 +80,7 @@ public void testExitFullscreenUsingRunnable() {
     @Test
     @SmallTest
     public void testExitFullscreenWhenTabDestroyed() {
+        enterFullscren();
         // Destroying the tab should exit fullscreen.
         TestThreadUtils.runOnUiThreadBlocking(
                 () -> { mActivity.getTab().getBrowser().destroyTab(mActivity.getTab()); });
@@ -88,6 +94,57 @@ public void testExitFullscreenWhenTabDestroyed() {
     @Test
     @SmallTest
     public void testDestroyFragmentWhileFullscreen() {
+        enterFullscren();
         TestThreadUtils.runOnUiThreadBlocking(() -> { mActivity.destroyFragment(); });
     }
+
+    // Waits for the top offset to go to -height. This means the view is completely hidden.
+    private final class BrowserControlsOffsetCallbackImpl extends BrowserControlsOffsetCallback {
+        private final CallbackHelper mCallbackHelper;
+        BrowserControlsOffsetCallbackImpl(CallbackHelper callbackHelper) {
+            mCallbackHelper = callbackHelper;
+        }
+        @Override
+        public void onTopViewOffsetChanged(int offset) {
+            int height = mActivity.getTopContentsContainer().getHeight();
+            if (height != 0 && offset == -height) {
+                mCallbackHelper.notifyCalled();
+            }
+        }
+    }
+
+    @Test
+    @SmallTest
+    public void testTopViewRemainsHiddenOnFullscreenRotation() throws Exception {
+        String url = mActivityTestRule.getTestDataURL("rotation2.html");
+        mActivity = mActivityTestRule.launchShellWithUrl(url);
+        // Ensure the fragment is not recreated as otherwise things bounce around more.
+        mActivityTestRule.setRetainInstance(true);
+        Assert.assertNotNull(mActivity);
+        mDelegate = new TestFullscreenCallback();
+        CallbackHelper callbackHelper = new CallbackHelper();
+        // The offsets may move around during rotation. Wait for reattachment before installing
+        // the BrowserControlsOffsetCallback.
+        InstrumentationActivity.registerOnCreatedCallback(
+                new InstrumentationActivity.OnCreatedCallback() {
+                    @Override
+                    public void onCreated(Browser browser) {
+                        browser.registerBrowserControlsOffsetCallback(
+                                new BrowserControlsOffsetCallbackImpl(callbackHelper));
+                    }
+                });
+        TestThreadUtils.runOnUiThreadBlocking(
+                () -> { mActivity.getTab().setFullscreenCallback(mDelegate); });
+
+        EventUtils.simulateTouchCenterOfView(mActivity.getWindow().getDecorView());
+        mDelegate.waitForFullscreen();
+        Assert.assertEquals(1, mDelegate.mEnterFullscreenCount);
+
+        // There should be a fullscreen element.
+        Assert.assertTrue(mActivityTestRule.executeScriptAndExtractBoolean(
+                "document.fullscreenElement != null"));
+
+        // Rotation should trigger the view being totally hidden.
+        callbackHelper.waitForFirst();
+    }
 }

weblayer/browser/java/org/chromium/weblayer_private/BrowserControlsContainerView.java

@@ -376,7 +376,12 @@ protected void onLayout(boolean changed, int left, int top, int right, int botto
         mLastHeight = height;
         if (mLastWidth > 0 && mLastHeight > 0 && mViewResourceAdapter == null) {
             createAdapterAndLayer();
-            if (mLastShownAmountWithView == DEFAULT_LAST_SHOWN_AMOUNT && mSavedState != null) {
+            if (mIsFullscreen) {
+                // This calls setControlsOffset() as onOffsetsChanged() does (mostly) nothing when
+                // fullscreen.
+                setControlsOffset(mIsTop ? -mLastHeight : mLastHeight, 0);
+            } else if (mLastShownAmountWithView == DEFAULT_LAST_SHOWN_AMOUNT
+                    && mSavedState != null) {
                 // If there wasn't a View before and we have non-empty saved state from a previous
                 // BrowserControlsContainerView instance, apply those saved offsets now. We can't
                 // rely on BrowserControlsOffsetManager to notify us of the correct location as we

weblayer/test/data/rotation2.html

@@ -0,0 +1,16 @@
+<html>
+  <body style="height:5000px">
+    <p>A page that will rotate on touch.</p>
+  </body>
+  <script>
+    async function toggleFullscreen() {
+      if (!document.fullscreenElement) {
+        await document.documentElement.requestFullscreen();
+        await screen.orientation.lock("landscape-primary");
+      } else {
+        document.exitFullscreen();
+      }
+    }
+    document.addEventListener('touchend', function(e) { toggleFullscreen(); }, false);
+  </script>
+</html>