Android: Don't check public apk proguard expectations when downstream play services is present

Noticed that the expectations were failing for no-op builds because of
this.

Bug: 882524
Change-Id: If0297c5e0ae0db61529089b6afbaaa430fa1ee01
Reviewed-on: https://chromium-review.googlesource.com/c/1407597
Commit-Queue: agrieve <agrieve@chromium.org>
Reviewed-by: Eric Stevenson <estevenson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622173}

build/android/gyp/util/diff_utils.py

@@ -5,7 +5,6 @@
 # found in the LICENSE file.
 
 import difflib
-import itertools
 
 
 def DiffFileContents(expected_path, actual_path, description):
@@ -24,9 +23,16 @@ def DiffFileContents(expected_path, actual_path, description):
       tofile=actual_path,
       n=0)
 
-  return '\n'.join(
-      itertools.chain(
-          diff, ('Detected {} change.'.format(description),
-                 'If this is expected, please update the file by running:',
-                 'cp {} {}'.format(actual_path, expected_path),
-                 'Otherwise please fix the issue before submitting a CL')))
+  return """
+Detected change in {}.
+If change is expected, please update the expectations by running:
+
+    cd out/Release
+    cp {} {}
+
+If you have hit this error on a bot and the error is for a public target,
+build locally with enable_chrome_android_internal=false.
+
+Here is the diff:
+{}
+""".format(description, actual_path, expected_path, '\n'.join(diff))

chrome/android/BUILD.gn

@@ -1485,7 +1485,10 @@ template("chrome_public_apk_or_module_tmpl") {
 chrome_public_apk_or_module_tmpl("chrome_public_apk") {
   target_type = "android_apk"
   apk_name = "ChromePublic"
-  if (!is_java_debug) {
+
+  # Having //clank present causes different flags because of how play services
+  # is wired up.
+  if (!is_java_debug && !enable_chrome_android_internal) {
     proguard_expectations_file =
         "//chrome/android/java/chrome_public_apk.proguard_flags.expected"
   }
@@ -1495,7 +1498,10 @@ chrome_public_apk_or_module_tmpl("chrome_modern_public_apk") {
   target_type = "android_apk"
   apk_name = "ChromeModernPublic"
   is_modern = true
-  if (!is_java_debug) {
+
+  # Having //clank present causes different flags because of how play services
+  # is wired up.
+  if (!is_java_debug && !enable_chrome_android_internal) {
     proguard_expectations_file =
         "//chrome/android/java/chrome_modern_public_apk.proguard_flags.expected"
   }
@@ -1590,7 +1596,10 @@ template("monochrome_public_apk_or_module_tmpl") {
 monochrome_public_apk_or_module_tmpl("monochrome_public_apk") {
   apk_name = "MonochromePublic"
   target_type = "android_apk"
-  if (!is_java_debug) {
+
+  # Having //clank present causes different flags because of how play services
+  # is wired up.
+  if (!is_java_debug && !enable_chrome_android_internal) {
     proguard_expectations_file =
         "//chrome/android/java/monochrome_public_apk.proguard_flags.expected"
   }