Adding workaround for issue with null drawable

A drawable is null which ought not be null, since it should have been set during inflation. Seems like a platform issue on one device. Adding a workaround to manually set it in code after inflation if necessary.

issue 15334203

Change-Id: Ideb80c231300e61f6dfe5336d6d647a3e1b51817
diff --git a/src/com/android/launcher3/InfoDropTarget.java b/src/com/android/launcher3/InfoDropTarget.java
index 374238c..fb623ca 100644
--- a/src/com/android/launcher3/InfoDropTarget.java
+++ b/src/com/android/launcher3/InfoDropTarget.java
@@ -49,6 +49,13 @@
         Resources r = getResources();
         mHoverColor = r.getColor(R.color.info_target_hover_tint);
         mDrawable = (TransitionDrawable) getCurrentDrawable();
+
+        if (mDrawable == null) {
+            // TODO: investigate why this is ever happening. Presently only on one known device.
+            mDrawable = r.getDrawable(R.drawable.info_target_selector);
+            setCompoundDrawablesRelativeWithIntrinsicBounds(mDrawable, null, null, null);
+        }
+
         if (null != mDrawable) {
             mDrawable.setCrossFadeEnabled(true);
         }