[Android] Eliminate JNI hop for critical path gestures

Previously, all gestures would pass through Java as they were filtered prior
to being forwarded to the renderer.  However, only a small subset of gestures
really need to be seen during this filtering phase.  The rest can be accommodated
simply by inspecting the corresponding gesture ack.  This saves ~20us per
GestureScrollUpdate and GesturePinchUpdate.

BUG=341613

Review URL: https://codereview.chromium.org/164643002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251181 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 31 insertions, 38 deletions

diff --git a/content/browser/android/content_view_core_impl.cc b/content/browser/android/content_view_core_impl.cc
index e981865..20eb17c 100644
--- a/content/browser/android/content_view_core_impl.cc
+++ b/content/browser/android/content_view_core_impl.cc
@@ -619,13 +619,19 @@ void ContentViewCoreImpl::OnGestureEventAck(const blink::WebGestureEvent& event,
     case WebInputEvent::GesturePinchEnd:
       Java_ContentViewCore_onPinchEndEventAck(env, j_obj.obj());
       break;
+    case WebInputEvent::GestureDoubleTap:
+      Java_ContentViewCore_onDoubleTapEventAck(env, j_obj.obj());
+      break;
     default:
       break;
   }
 }
 
 bool ContentViewCoreImpl::FilterInputEvent(const blink::WebInputEvent& event) {
-  if (!WebInputEvent::isGestureEventType(event.type))
+  if (event.type != WebInputEvent::GestureTap &&
+      event.type != WebInputEvent::GestureDoubleTap &&
+      event.type != WebInputEvent::GestureLongTap &&
+      event.type != WebInputEvent::GestureLongPress)
     return false;
 
   JNIEnv* env = AttachCurrentThread();
@@ -636,11 +642,11 @@ bool ContentViewCoreImpl::FilterInputEvent(const blink::WebInputEvent& event) {
   const blink::WebGestureEvent& gesture =
       static_cast<const blink::WebGestureEvent&>(event);
   int gesture_type = ToContentViewGestureHandlerType(event.type);
-  return Java_ContentViewCore_filterGestureEvent(env,
-                                                 j_obj.obj(),
-                                                 gesture_type,
-                                                 gesture.x,
-                                                 gesture.y);
+  return Java_ContentViewCore_filterTapOrPressEvent(env,
+                                                    j_obj.obj(),
+                                                    gesture_type,
+                                                    gesture.x,
+                                                    gesture.y);
 }
 
 bool ContentViewCoreImpl::HasFocus() {
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index 11cfc9a..3ee52e8 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -1232,6 +1232,7 @@ public class ContentViewCore
     @SuppressWarnings("unused")
     @CalledByNative
     private void onFlingStartEventConsumed(int vx, int vy) {
+        temporarilyHideTextHandles();
         for (mGestureStateListenersIterator.rewind();
                     mGestureStateListenersIterator.hasNext();) {
             mGestureStateListenersIterator.next().onFlingStartGesture(
@@ -1257,12 +1258,15 @@ public class ContentViewCore
     @SuppressWarnings("unused")
     @CalledByNative
     private void onScrollBeginEventAck() {
+        temporarilyHideTextHandles();
+        mZoomControlsDelegate.invokeZoomPicker();
         updateGestureStateListener(GestureEventType.SCROLL_START);
     }
 
     @SuppressWarnings("unused")
     @CalledByNative
     private void onScrollUpdateGestureConsumed() {
+        mZoomControlsDelegate.invokeZoomPicker();
         for (mGestureStateListenersIterator.rewind();
                 mGestureStateListenersIterator.hasNext();) {
             mGestureStateListenersIterator.next().onScrollUpdateGestureConsumed();
@@ -1278,6 +1282,7 @@ public class ContentViewCore
     @SuppressWarnings("unused")
     @CalledByNative
     private void onPinchBeginEventAck() {
+        temporarilyHideTextHandles();
         updateGestureStateListener(GestureEventType.PINCH_BEGIN);
     }
 
@@ -1287,21 +1292,23 @@ public class ContentViewCore
         updateGestureStateListener(GestureEventType.PINCH_END);
     }
 
+    @SuppressWarnings("unused")
+    @CalledByNative
+    private void onDoubleTapEventAck() {
+        temporarilyHideTextHandles();
+    }
+
     /**
-     * Called just prior to a gesture being forwarded to the renderer. All listening
-     * for the sending of (synthetic or touch-derived) gestures should occur here.
+     * Called just prior to a tap or press gesture being forwarded to the renderer.
      */
     @SuppressWarnings("unused")
     @CalledByNative
-    private boolean filterGestureEvent(int type, int x, int y) {
-        if (offerGestureToEmbedder(type)) return true;
-        updateTextHandlesForGesture(type);
+    private boolean filterTapOrPressEvent(int type, int x, int y) {
+        if (type == GestureEventType.LONG_PRESS && offerLongPressToEmbedder()) {
+            return true;
+        }
         updateForTapOrPress(type, x, y);
         updateForDoubleTapUMA(type);
-        // TODO(jdduke): Determine if this should be called while a pinch is active.
-        if (type == GestureEventType.SCROLL_BY) {
-            mZoomControlsDelegate.invokeZoomPicker();
-        }
         return false;
     }
 
@@ -2393,20 +2400,6 @@ public class ContentViewCore
         return mInsertionHandleController != null && mInsertionHandleController.isShowing();
     }
 
-    private void updateTextHandlesForGesture(int type) {
-        switch(type) {
-            case GestureEventType.DOUBLE_TAP:
-            case GestureEventType.SCROLL_START:
-            case GestureEventType.FLING_START:
-            case GestureEventType.PINCH_BEGIN:
-                temporarilyHideTextHandles();
-                break;
-
-            default:
-                break;
-        }
-    }
-
     // Makes the insertion/selection handles invisible. They will fade back in shortly after the
     // last call to scheduleTextHandleFadeIn (or temporarilyHideTextHandles).
     private void temporarilyHideTextHandles() {
@@ -3265,18 +3258,12 @@ public class ContentViewCore
     }
 
     /**
-     * Offer a subset of gesture events to the embedding View,
-     * primarily for WebView compatibility.
-     *
-     * @param type The type of the event.
+     * Offer a long press gesture to the embedding View, primarily for WebView compatibility.
      *
      * @return true if the embedder handled the event.
      */
-    private boolean offerGestureToEmbedder(int type) {
-        if (type == GestureEventType.LONG_PRESS) {
-            return mContainerView.performLongClick();
-        }
-        return false;
+    private boolean offerLongPressToEmbedder() {
+        return mContainerView.performLongClick();
     }
 
     private native long nativeInit(long webContentsPtr,