Define proprietary_codecs=1 when branding==Chrome.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index bb7fabd47dae7fdd01bbc8d70568f9a5f754f3f9..062b0584c21fe11a7ed9e5765b4e3dc4fdafe4ee 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -526,7 +526,6 @@
           'enable_printing%': 0,
           'enable_spellcheck%': 0,
           'enable_themes%': 0,
-          'proprietary_codecs%': 1,
           'remoting%': 0,
           'arm_neon%': 0,
           'arm_neon_optional%': 1,
@@ -534,6 +533,13 @@
           'native_memory_pressure_signals%': 1,
         }],
 
+        # Android OS includes support for proprietary codecs regardless of
+        # building Chromium or Google Chrome. We also ship Google Chrome with
+        # proprietary codecs.
+        ['OS=="android" or branding=="Chrome"', {
+          'proprietary_codecs%': 1,
+        }],
+
         # Enable autofill dialog for Android, Mac and Views-enabled platforms.
         ['toolkit_views==1 or (OS=="android" and android_webview_build==0) or OS=="mac"', {
           'enable_autofill_dialog%': 1