Add a view to show magnified link preview on Andrdoid.

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

Index: content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
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 09ac6d47356a3091707ecbe342bfc5b1a6c68c24..5f6c6c3a178fdbe108881ab78fdc7ddd0eacffa0 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
@@ -24,15 +24,14 @@ import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 import org.chromium.base.WeakContext;
 import org.chromium.content.app.AppResource;
+import org.chromium.content.browser.accessibility.AccessibilityInjector;
 import org.chromium.content.browser.ContentViewGestureHandler;
+import org.chromium.content.browser.ContentViewGestureHandler.MotionEventDelegate;
 import org.chromium.content.browser.TouchPoint;
 import org.chromium.content.browser.ZoomManager;
 import org.chromium.content.common.CleanupReference;
 import org.chromium.content.common.TraceEvent;
 
-import org.chromium.content.browser.accessibility.AccessibilityInjector;
-import org.chromium.content.browser.ContentViewGestureHandler.MotionEventDelegate;
-
 /**
  * Provides a Java-side 'wrapper' around a WebContent (native) instance.
  * Contains all the major functionality necessary to manage the lifecycle of a ContentView without
@@ -163,6 +162,8 @@ public class ContentViewCore implements MotionEventDelegate {
     private float mNativeMinimumScale = 1.0f;
     private float mNativeMaximumScale = 1.0f;
 
+    private PopupZoomer mPopupZoomer;
+
     // TODO(klobag): this is to avoid a bug in GestureDetector. With multi-touch,
     // mAlwaysInTapRegion is not reset. So when the last finger is up, onSingleTapUp()
     // will be mistakenly fired.
@@ -295,9 +296,38 @@ public class ContentViewCore implements MotionEventDelegate {
         mZoomManager.updateMultiTouchSupport();
         mContentViewGestureHandler = new ContentViewGestureHandler(context, this, mZoomManager);
 
+        initPopupZoomer(mContext);
+
         Log.i(TAG, "mNativeContentView=0x"+ Integer.toHexString(mNativeContentViewCore));
     }
 
+    private void initPopupZoomer(Context context){
+        assert AppResource.DIMENSION_LINK_PREVIEW_OVERLAY_RADIUS != 0;
+        mPopupZoomer = new PopupZoomer(context, AppResource.DIMENSION_LINK_PREVIEW_OVERLAY_RADIUS);
+        mContainerView.addView(mPopupZoomer);
+        PopupZoomer.OnTapListener listener = new PopupZoomer.OnTapListener() {
+            @Override
+            public boolean onSingleTap(View v, MotionEvent e) {
+                mContainerView.requestFocus();
+                if (mNativeContentViewCore != 0) {
+                    nativeSingleTap(mNativeContentViewCore, e.getEventTime(), (int) e.getX(),
+                            (int) e.getY(), true);
+                }
+                return true;
+            }
+
+            @Override
+            public boolean onLongPress(View v, MotionEvent e) {
+                if (mNativeContentViewCore != 0) {
+                    nativeLongPress(mNativeContentViewCore, e.getEventTime(), (int) e.getX(),
+                            (int) e.getY(), true);
+                }
+                return true;
+            }
+        };
+        mPopupZoomer.setOnTapListener(listener);
+    }
+
     /**
      * @return Whether the configured personality of this ContentView is {@link #PERSONALITY_VIEW}.
      */
@@ -702,6 +732,8 @@ public class ContentViewCore implements MotionEventDelegate {
         //TODO(yusufo):Upstream the rest of the bits about handlerControllers.
         if (!mContainerView.isFocused()) mContainerView.requestFocus();
 
+        if (!mPopupZoomer.isShowing()) mPopupZoomer.setLastTouch(x, y);
+
         if (isLongPress) {
             if (mNativeContentViewCore != 0) {
                 nativeLongPress(mNativeContentViewCore, timeMs, x, y, false);