*** Reason for rollback ***
Broke everything
*** Original change description ***
Clean up message naming in EPII
***
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184061352
1. When we try and load something via reflection and find the
class, always throw rather than failing silently if we
subsequently fail to instantiate an instance. This is
indicative of a broken proguard setup, and failing silently
makes it hard to spot.
2. Add library/core proguard configuration to ensure extension
renderer constructors that we access via reflection are kept.
3. Add demos/main proguard configuration to ensure ImaAdsLoader
constructor that we access via reflection is kept.
4. Added IMA proguard file to hopefully fix#3723, although I
wasn't actually able to reproduce the issue.
Issue: #3723
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183648187