Fix dom_perf.py against r238298.

TBR=tonyg@chromium.org
NOTRY=True
BUG=None
TEST=None

Review URL: https://codereview.chromium.org/100603003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238305 0039d316-1c4b-4281-b951-d872f2087c98

tools/perf/benchmarks/dom_perf.py

@@ -75,7 +75,7 @@ class DomPerf(test.Test):
   means better performance: Bigger is better!"""
   test = _DomPerfMeasurement
 
-  enabled = not sys.platform.startwith('linux')
+  enabled = not sys.platform.startswith('linux')
 
   def CreatePageSet(self, options):
     dom_perf_dir = os.path.join(util.GetChromiumSrcDir(), 'data', 'dom_perf')