Moving flags out of base_proguard_config make it usable by other .apks

base/android/base_proguard_config.flags

Index: base/android/base_proguard_config.flags
diff --git a/base/android/base_proguard_config.flags b/base/android/base_proguard_config.flags
index 6ff4351aee1f09ae8736d379b84db8ff6207a6b3..f69f09cfb4bc806df4a78a207cd448e6684b8e2e 100644
--- a/base/android/base_proguard_config.flags
+++ b/base/android/base_proguard_config.flags
@@ -51,27 +51,6 @@
   static *** isLoggable(...);
 }
 
-# The following chart was created on July 20, 2016, to decide on 3 optimization
-# passes.
-# optimization passes | time | .dex size | dirty memory per process
-# -----------------------------------------------------------------
-#          1          | 0:48 |  5805676  |         488972
-#          2          | 1:07 |  5777376  |         487092
-#          3          | 1:24 |  5772192  |         486596
-#          4          | 1:42 |  5771124  |         486484
-#          5          | 1:56 |  5770504  |         486432
--optimizationpasses 3
-
-# Class merging provides negligible .dex size reduction and method count
-# reduction (about 0.3% improvement on method count, and 0.1% savings on size),
-# and it messes up stack traces if the classes are optimized. Thus, it is in our
-# best interests to turn it off. See crbug.com/620323
--optimizations !class/merging/*
-
-# Allowing Proguard to change modifiers. This change shrinks the .dex size by
-# ~1.1%, and reduces the method count by ~4.3%.
--allowaccessmodification
-
 # Keep all enum values and valueOf methods. See
 # http://proguard.sourceforge.net/index.html#manual/examples.html
 # for the reason for this. Also, see http://crbug.com/248037.