Avoid silently using the wrong flags file for apk-under-test.

Bug: 996501
Change-Id: I664ebb130f949b9f4ccb0c24fd760c56db8cb0de
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1764869
Commit-Queue: Andrew Luo <aluo@chromium.org>
Reviewed-by: Ben Pastene <bpastene@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690013}

build/android/pylib/constants/__init__.py

@@ -67,6 +67,10 @@ PACKAGE_INFO.update({
     chrome.PackageInfo('com.android.webview',
                        'com.android.cts.webkit.WebViewStartupCtsActivity',
                        'webview-command-line', None),
+    'android_google_webview_cts':
+    chrome.PackageInfo('com.google.android.webview',
+                       'com.android.cts.webkit.WebViewStartupCtsActivity',
+                       'webview-command-line', None),
 })
 
 

build/android/pylib/local/device/local_device_instrumentation_test_run.py

@@ -398,9 +398,8 @@ class LocalDeviceInstrumentationTestRun(
         if self._test_instance.package_info:
           cmdline_file = self._test_instance.package_info.cmdline_file
         else:
-          logging.warning(
-              'No PackageInfo found, falling back to using flag file %s',
-              cmdline_file)
+          raise Exception('No PackageInfo found but'
+                          '--use-apk-under-test-flags-file is specified.')
       self._flag_changers[str(device)] = flag_changer.FlagChanger(
           device, cmdline_file)