Create HTTP-based GM results viewer.

For now, it only allows VIEWING results... next, it will allow the user to
rebaseline GM results via the web interface.

R=borenet@google.com

Review URL: https://codereview.chromium.org/24274003

git-svn-id: http://skia.googlecode.com/svn/trunk@11500 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tools/svn.py b/tools/svn.py
index 9b60413..72d8ad8 100644
--- a/tools/svn.py
+++ b/tools/svn.py
@@ -85,6 +85,15 @@
         """
         return self._RunCommand([SVN, 'checkout', url, path])
 
+    def Update(self, path):
+        """Update the working copy.
+        Returns stdout as a single string.
+
+        @param path path (within self._directory) within which to run
+        "svn update"
+        """
+        return self._RunCommand([SVN, 'update', path])
+
     def ListSubdirs(self, url):
         """Returns a list of all subdirectories (not files) within a given SVN
         url.