Revert "Separate Canvas JNI code from the implementation."

This reverts commit e28a5afee885cd69a5be5809f88116b601cb1a72.

 Appears to cause memory corruption and random appearances of
 chinese

 Bug: 16343240
 Bug: 16336642

Change-Id: Ife169181f40adff4b12948ed5f9d3a88dcec935b
14 files changed