fix [2599939] "cannot play video" after open/close a video player a dozen of times

get rid off the MAP_ONCE flag is MemoryHeapBase (as well as it's functionality),
this feature should not be used anymore.

the software renderer was incorrectly using the default ctor which set MAP_ONCE,
causing the leak. the software renderer itself is incorrectly used while coming
back from sleep.

Change-Id: I123621f8d140550b864f352bbcd8a5729db12b57
diff --git a/include/binder/MemoryHeapPmem.h b/include/binder/MemoryHeapPmem.h
index aac164f..e1660c4 100644
--- a/include/binder/MemoryHeapPmem.h
+++ b/include/binder/MemoryHeapPmem.h
@@ -46,8 +46,7 @@
         sp<MemoryHeapPmem>  mClientHeap;
     };
     
-    MemoryHeapPmem(const sp<MemoryHeapBase>& pmemHeap,
-                uint32_t flags = IMemoryHeap::MAP_ONCE);
+    MemoryHeapPmem(const sp<MemoryHeapBase>& pmemHeap, uint32_t flags = 0);
     ~MemoryHeapPmem();
 
     /* HeapInterface additions */