add new test targets in chromium_builder_dbg_drmemory_win for DrMemory build

- add gpu_unittests

R=bruening@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/233393005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263053 0039d316-1c4b-4281-b951-d872f2087c98

build/all.gyp

@@ -1068,6 +1068,7 @@
             '../media/media.gyp:media_unittests',
             '../net/net.gyp:net_unittests',
             '../google_apis/gcm/gcm.gyp:gcm_unit_tests',
+            '../gpu/gpu.gyp:gpu_unittests',
             '../printing/printing.gyp:printing_unittests',
             '../remoting/remoting.gyp:remoting_unittests',
             '../sql/sql.gyp:sql_unittests',