Fix enum field references with java_multiple_files.

When the java_multiple_files option is on, enums are placed in java
class files based on the name of the original enum type. This fixes
field references to such enum values to point to the correct class
name when setting the default.

Change-Id: I51a2e251c0d0ab1e45a182ba849d314232a74bac
2 files changed