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/IMemory.h b/include/binder/IMemory.h
index ae042cb..74d2cc7 100644
--- a/include/binder/IMemory.h
+++ b/include/binder/IMemory.h
@@ -36,8 +36,7 @@
 
     // flags returned by getFlags()
     enum {
-        READ_ONLY   = 0x00000001,
-        MAP_ONCE    = 0x00000002
+        READ_ONLY   = 0x00000001
     };
 
     virtual int         getHeapID() const = 0;