Add Pdfium to list of can-be-patched projects in chromium checkout.

R=machenbach@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1914123002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300185 0039d316-1c4b-4281-b951-d872f2087c98

recipe_modules/gclient/config.py

@@ -166,6 +166,7 @@ def chromium_bare(c):
   p['v8'] = ('src/v8', 'HEAD')
   p['angle/angle'] = ('src/third_party/angle', None)
   p['blink'] = ('src/third_party/WebKit', None)
+  p['pdfium'] = ('src/third_party/pdfium', 'HEAD')
 
 @config_ctx(includes=['chromium_bare'])
 def chromium_empty(c):