Fixing wrong padding being set in multi-window + landscape

In multi-window, we only have the correct availableWidth and not the correct width.
Use availableWidth for setting padding instead of fullWidth

Change-Id: Id437088eea49ab5ad103ded6eed904d776e728c9
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index 4263654..a7dd5e3 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -453,11 +453,12 @@
         mInsets.set(insets);
         DeviceProfile dp = mActivity.getDeviceProfile();
         getTaskSize(dp, mTempRect);
+
         mTempRect.top -= getResources()
                 .getDimensionPixelSize(R.dimen.task_thumbnail_top_margin);
         setPadding(mTempRect.left - mInsets.left, mTempRect.top - mInsets.top,
-                dp.widthPx - mTempRect.right - mInsets.right,
-                dp.heightPx - mTempRect.bottom - mInsets.bottom);
+                dp.availableWidthPx + mInsets.left - mTempRect.right,
+                dp.availableHeightPx + mInsets.top - mTempRect.bottom);
     }
 
     protected abstract void getTaskSize(DeviceProfile dp, Rect outRect);