Update --force-fieldtrial-params comment to be a little more clear.

chrome/common/chrome_switches.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/chrome_switches.h"
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "build/build_config.h"
 
@@ skipping 573 matching lines @@
 // If this flag is present then this command line is being delegated to an
 // already running chrome process via the fast path, ie: before chrome.dll is
 // loaded. It is useful to tell the difference for tracking purposes.
 const char kFastStart[]            = "fast-start";
 
 // Forces application mode. This hides certain system UI elements and forces
 // the app to be installed if it hasn't been already.
 const char kForceAppMode[]                  = "force-app-mode";
 
 // This option can be used to force parameters of field trials when testing
-// changes locally. The argument is a list of key/value pairs prefixed by
-// Trial/Group pair. The following shows setting parameters to 2 experiments
-// where in the first, it forces "id" to be "foo" for the "Enabled" group of
-// the "EnhancedBookmarks" trial:
-// "EnhancedBookmarks.Enabled:id/foo,Experiment2.Group1:key1/value1"
+// changes locally. The argument is param list of key/value pairs prefixed by an

[Alexei Svitkine (slow), 2016/02/10 17:34:46]

Nit: The argument is a param list

(Missing "a")

[danduong, 2016/02/10 18:19:53]

Done.

+// associated Trial/Group pair. You specify the param list for multiple
+// Trial/Groups with a comma separator.
+// Example:
+//   "Trial1.Group1:k1/v1/k2/v2,Trial2.Group2:k3/v3/k4/v4"
 // Trial names, groups names, parameter names, and value should all be URL
 // escaped for all non-alphanumeric characters.
 const char kForceFieldTrialParams[] = "force-fieldtrial-params";
 
 // Displays the First Run experience when the browser is started, regardless of
 // whether or not it's actually the First Run (this overrides kNoFirstRun).
 const char kForceFirstRun[]                 = "force-first-run";
 
 // Forces additional Chrome Variation Ids that will be sent in X-Client-Data
 // header, specified as a 64-bit encoded list of numeric experiment ids. Ids
@@ skipping 774 matching lines @@
 
 // -----------------------------------------------------------------------------
 // DO NOT ADD YOUR CRAP TO THE BOTTOM OF THIS FILE.
 //
 // You were going to just dump your switches here, weren't you? Instead, please
 // put them in alphabetical order above, or in order inside the appropriate
 // ifdef at the bottom. The order should match the header.
 // -----------------------------------------------------------------------------
 
 }  // namespace switches