Get rid of dependency on android-common

It was only used for a single string constant that can be inlined

Change-Id: I19078b6b00adf1b91e329d10181e91809944b606
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 3f487cd..0486b00 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -94,7 +94,6 @@
 import android.widget.TextView;
 import android.widget.Toast;
 
-import com.android.common.Search;
 import com.android.launcher3.R;
 import com.android.launcher3.DropTarget.DragObject;
 
@@ -1620,7 +1619,7 @@
         }
         if (appSearchData == null) {
             appSearchData = new Bundle();
-            appSearchData.putString(Search.SOURCE, "launcher-search");
+            appSearchData.putString("source", "launcher-search");
         }
         Rect sourceBounds = new Rect();
         if (mSearchDropTargetBar != null) {