No longer call registerNativeAllocation

The original rationale is obsolete, since contexts are now almost
always shared.

This call was unbalanced; there was no corresponding
freeNativeAllocation call. Thus, in the rare cases in which this
actually makes a difference, it's likely to lead to perpetually
increasing native allocation counts, which is more likely to be
confusing than helpful to the garbage collector.

(Discussed with Tim and Jean-Luc, and concluded that it was best
just to remove the code.)

Test: Treehugger
Bug: 181351667
Change-Id: I376a16732231aad0fdacd022de301464e5ac71dd

rs/java/android/renderscript/RenderScript.java

@@ -1363,13 +1363,6 @@ public class RenderScript {
             mApplicationContext = ctx.getApplicationContext();
         }
         mRWLock = new ReentrantReadWriteLock();
-        try {
-            registerNativeAllocation.invoke(sRuntime, 4 * 1024 * 1024); // 4MB for GC sake
-        } catch (Exception e) {
-            Log.e(RenderScript.LOG_TAG, "Couldn't invoke registerNativeAllocation:" + e);
-            throw new RSRuntimeException("Couldn't invoke registerNativeAllocation:" + e);
-        }
-
     }
 
     /**