Intercept touch events for launcher preview root view

This change prevents any accidental touches on any widgets in the
preview.

Test: Tapping on launcher preview in wallpaper app should never activate
a widget.
Fix: 191623924

Change-Id: Iac7eab057ec33ff491365a993af75a0b06a27f7e
Merged-In: I98d462eca699cf368dcd5894f15584f280932ccc

res/layout/launcher_preview_layout.xml

@@ -13,7 +13,7 @@
      See the License for the specific language governing permissions and
      limitations under the License.
 -->
-<com.android.launcher3.InsettableFrameLayout
+<view class="com.android.launcher3.graphics.LauncherPreviewRenderer$LauncherPreviewLayout"
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:launcher="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
@@ -33,4 +33,4 @@
         android:id="@+id/hotseat"
         layout="@layout/hotseat" />
 
-</com.android.launcher3.InsettableFrameLayout>
+</view>

src/com/android/launcher3/graphics/LauncherPreviewRenderer.java

@@ -43,6 +43,7 @@ import android.os.Process;
 import android.util.AttributeSet;
 import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
+import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.WindowInsets;
@@ -467,4 +468,16 @@ public class LauncherPreviewRenderer extends ContextWrapper
         view.measure(makeMeasureSpec(width, EXACTLY), makeMeasureSpec(height, EXACTLY));
         view.layout(0, 0, width, height);
     }
+
+    /** Root layout for launcher preview that intercepts all touch events. */
+    public static class LauncherPreviewLayout extends InsettableFrameLayout {
+        public LauncherPreviewLayout(Context context, AttributeSet attrs) {
+            super(context, attrs);
+        }
+
+        @Override
+        public boolean onInterceptTouchEvent(MotionEvent ev) {
+            return true;
+        }
+    }
 }