Fix ordering of fields with the same name.

Fix ordering of fields with the same name.

While the Java language doesn't allow multiple fields with
the same name in a single class (excluding fields from super
classes), the bytecode specification permits it and tools
such as proguard actually generate them. Define the order of
these fields by their dex file index and relax the check of
field ordering to permit identical names.

Bug: 18211592
Change-Id: I1dee9b2b669a6ea180a2d3a41030efb2aed53950