This CL replaces the copy constructor
MediaMetadata(MediaMetadata source, int maxBitmapSize)
with the new public method Builder#setBitmapDimensionLimit().
Also added a getter getBitmapDimensionLimit().
Bug: 168215839
Test: m update-api -j; Ran MediaMetdataTest
Change-Id: I6844fcf01c4ee98c99bd0dc880b96f73989dbd3c