Temporal edge navigation feature

- User can swipe from left and right edge to go
  back and forward in history of a tab

Change-Id: I941f91122510b004bdcb6a718eb6c05730694960
diff --git a/src/com/android/browser/DraggableFrameLayout.java b/src/com/android/browser/DraggableFrameLayout.java
new file mode 100644
index 0000000..e2f9699
--- /dev/null
+++ b/src/com/android/browser/DraggableFrameLayout.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials provided
+ *       with the distribution.
+ *     * Neither the name of The Linux Foundation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.android.browser;
+
+import android.content.Context;
+import android.support.v4.view.ViewCompat;
+import android.support.v4.widget.ViewDragHelper;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.view.MotionEvent;
+import android.view.ViewGroup;
+import android.widget.FrameLayout;
+
+public class DraggableFrameLayout extends FrameLayout {
+    private ViewDragHelper mDragger;
+    public DraggableFrameLayout(Context ctx) {
+        super(ctx);
+    }
+    public DraggableFrameLayout(Context ctx, AttributeSet set) {
+        super(ctx, set);
+    }
+    public DraggableFrameLayout(Context ctx, AttributeSet set, int defStyleAttr) {
+        super(ctx, set, defStyleAttr);
+    }
+    public DraggableFrameLayout(Context ctx, AttributeSet set, int defStyleAttr, int defStyleRes) {
+        super(ctx, set, defStyleAttr, defStyleRes);
+    }
+
+    public void setDragHelper(ViewDragHelper dragger) {
+        mDragger = dragger;
+    }
+
+    public final ViewGroup getParentViewGroup() {
+        return (ViewGroup) DraggableFrameLayout.this.getParent();
+    }
+
+    @Override
+    public boolean onInterceptTouchEvent(MotionEvent event) {
+        if (mDragger == null)
+            return super.onInterceptTouchEvent(event);
+
+        return mDragger.shouldInterceptTouchEvent(event) ?
+                true : super.onInterceptTouchEvent(event);
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent event) {
+        if (mDragger == null)
+            return super.onTouchEvent(event);
+
+        mDragger.processTouchEvent(event);
+        return true;
+    }
+
+    @Override
+    public void computeScroll() {
+        super.computeScroll();
+        if (mDragger != null && mDragger.continueSettling(true)) {
+            ViewCompat.postInvalidateOnAnimation(this);
+        }
+    }
+}
+