Add WebKit/Tools/Scripts to support Android test execution.

In https://code.google.com/p/webrtc/source/detail?r=4038 we rolled
chromium_revision past the point where WebKit/Tools/Scripts had its
own DEP in the Chromium DEPS file.
Since Chromium now only have a single WebKit checkout, we need to
pull the Tools/Scripts dir to be able to use the Android test
framework (build/android/run_test.py) since it's depending on modules
in webkitpy.

I have filed http://crbug.com/246529 to get this dependency removed.

BUG=1882
TEST=build/android/run_tests.py executes without any import errors.
R=fischman@webrtc.org, niklas.enbom@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1608004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4173 4adac7df-926f-26a2-2b94-8c16560cd09d

DEPS

@@ -15,6 +15,9 @@ vars = {
   # External resources like video and audio files used for testing purposes.
   # Downloaded on demand when needed.
   "webrtc_resources_revision": "16",
+
+  # A small subset of WebKit is needed for the Android Python test framework.
+  "webkit_trunk": "http://src.chromium.org/blink/trunk",
 }
 
 # NOTE: Prefer revision numbers to tags for svn deps. Use http rather than
@@ -115,6 +118,9 @@ deps_os = {
 
     "third_party/android_testrunner":
       Var("chromium_trunk") + "/src/third_party/android_testrunner@" + Var("chromium_revision"),
+
+    "third_party/WebKit/Tools/Scripts":
+      Var("webkit_trunk") + "/Tools/Scripts@151677",
   },
 }