Add shared preference file modification option to instrumentation test runner

build/android/test_runner.py

Index: build/android/test_runner.py
diff --git a/build/android/test_runner.py b/build/android/test_runner.py
index 08ec868e2b55155acc85e226f9088fae6134bda1..99711722442a312ce6ce0a519f62a3275c0f5bf1 100755
--- a/build/android/test_runner.py
+++ b/build/android/test_runner.py
@@ -400,6 +400,22 @@ def AddInstrumentationTestOptions(parser):
   group.add_argument('--store-tombstones', dest='store_tombstones',
                      action='store_true',
                      help='Add tombstones in results if crash.')
+  group.add_argument('--shared-prefs-file', dest='shared_prefs_file',
+                     type=os.path.realpath,
+                     help='The relative path to a file containing JSON list '
+                          'of shared preference files to edit and how to do '
+                          'so. Example list: '
+                          '[{'
+                          '  "package": "com.package.example",'
+                          '  "filename": "ExampleSettings.xml",'
+                          '  "set": {'
+                          '    "boolean_key_in_xml": true,'
+                          '    "string_key_in_xml": "string_value"'
+                          '  },'
+                          '  "remove": ['
+                          '    "key_in_xml_to_remove"'
+                          '  ]'
+                          '}]')
 
   AddCommonOptions(parser)
   AddDeviceOptions(parser)