Gallery2: add deadzone for video scroll gestures

Make the top 1/4 of the screen not respond to brightness/volume/seek
gestures, to allow dragging down statusbar without changing them.
Also increase the gesture treshold.

Change-Id: Ibc4241071dc3bf6702cec191c72751829c779ea8
diff --git a/src/com/android/gallery3d/app/GestureController.java b/src/com/android/gallery3d/app/GestureController.java
index 22deb67..7a549ee 100644
--- a/src/com/android/gallery3d/app/GestureController.java
+++ b/src/com/android/gallery3d/app/GestureController.java
@@ -35,7 +35,7 @@
 import android.view.MotionEvent;
 
 public class GestureController {
-    private static final int GESTURE_THRESHOLD = 20;
+    private static final int GESTURE_THRESHOLD = 40;
     private GestureDetector mGestureDetector;
     private GestureControlListener mGestureControlListener;
 
diff --git a/src/com/android/gallery3d/app/GestureControllerOverlay.java b/src/com/android/gallery3d/app/GestureControllerOverlay.java
index eac8376..f73dc76 100755
--- a/src/com/android/gallery3d/app/GestureControllerOverlay.java
+++ b/src/com/android/gallery3d/app/GestureControllerOverlay.java
@@ -168,13 +168,13 @@
 
     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
-        if (changed && mGestureController != null) {
-            mGestureController.setRect(left, top, right, bottom);
-        }
-
         int h = bottom - top;
         int w = right - left;
 
+        if (changed && mGestureController != null) {
+            mGestureController.setRect(left, top + h / 4, right, bottom);
+        }
+
         if (mCurrentIndicator != null) {
             layoutCenteredView(mCurrentIndicator, 0, 0, w, h);
         }