Creating new gn arg: enable_all_proguard_optimizations.

build/config/android/config.gni

Index: build/config/android/config.gni
diff --git a/build/config/android/config.gni b/build/config/android/config.gni
index 3590205c37b8057ede2f66c78cd6eb59b16b5093..3a62c216c18bd0d4fc94f645695b79da95e2bfb9 100644
--- a/build/config/android/config.gni
+++ b/build/config/android/config.gni
@@ -124,23 +124,35 @@ if (is_android) {
     # Required for Android M+ due to SELinux policies (stronger sandboxing).
     disable_incremental_isolated_processes = false
 
+    # Enables all ProGuard optimizations. These optimizations must not be
+    # enabled for instrumentation tests, since they cause code required by the
+    # tests to be removed.
+    # TODO(smaier): when buildbots get updated to set this flag, change the
+    # default to is_official_build
+    enable_all_proguard_optimizations = false
+
     # Speed up incremental compiles by compiling only changed files.
     enable_incremental_javac = false
 
     # Speed up dexing using dx --incremental.
     enable_incremental_dx = is_java_debug
 
-    # Neither of these should ever be used for release builds since they are
-    # somewhat experimental and dx --incremental is known to not produce
-    # byte-for-byte identical output.
-    assert(!(enable_incremental_dx && !is_java_debug))
-    assert(!(enable_incremental_javac && !is_java_debug))
-
     # Adds intrumentation to each function. Writes a file with the order that
     # functions are called at startup.
     use_order_profiling = false
   }
 
+  # Ensuring we never have a situation where we are asking to have debug java
+  # on alongside all ProGuard optimizations turned on, as these are mutually
+  # exclusive.
+  assert(!(is_java_debug && enable_all_proguard_optimizations))
+
+  # Neither of these should ever be used for release builds since they are
+  # somewhat experimental and dx --incremental is known to not produce
+  # byte-for-byte identical output.
+  assert(!(enable_incremental_dx && !is_java_debug))
+  assert(!(enable_incremental_javac && !is_java_debug))
+
   # Host stuff -----------------------------------------------------------------
 
   # Defines the name the Android build gives to the current host CPU