Partial cp of "Prepare role code for modularization."

This keeps MainThread building against core_current.

Test: m framework-annotations-lib
Merged-In: I74f20b37d23370e258e7fc7130e28c5312abf46c
Change-Id: Iaa9833a5615c80b58e64975d4f0f0e38a5e76a3e

core/java/android/annotation/MainThread.java

@@ -21,8 +21,6 @@ import static java.lang.annotation.ElementType.PARAMETER;
 import static java.lang.annotation.ElementType.TYPE;
 import static java.lang.annotation.RetentionPolicy.SOURCE;
 
-import android.os.Looper;
-
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
@@ -40,8 +38,7 @@ import java.lang.annotation.Target;
  * </code>
  * </pre>
  *
- * @memberDoc This method must be called from the
- *            {@linkplain Looper#getMainLooper() main thread} of your app.
+ * @memberDoc This method must be called from the main thread of your app.
  * @hide
  */
 @Retention(SOURCE)