Adding knobs on HQP provider.

components/omnibox/omnibox_field_trial.h

Index: components/omnibox/omnibox_field_trial.h
diff --git a/components/omnibox/omnibox_field_trial.h b/components/omnibox/omnibox_field_trial.h
index 5a439e2f384a6dd62e2d1a5ceba56938d58b8325..fbc0bdde274714f1049738847c5699ebe7f9eddf 100644
--- a/components/omnibox/omnibox_field_trial.h
+++ b/components/omnibox/omnibox_field_trial.h
@@ -270,6 +270,20 @@ class OmniboxFieldTrial {
                                         int* polling_delay_ms);
 
   // ---------------------------------------------------------
+  // For HQP related experiments.

[Mark P, 2015/02/11 21:57:30]

please make this comment clearer about what this section is.  (There are other
"HQP related" experiments in this file.)

[Ashok vardhan, 2015/02/12 19:56:32]

Done.

+  //

[Mark P, 2015/02/11 21:57:30]

nit: want a blank line without a // here, like all other sections

[Ashok vardhan, 2015/02/12 19:56:32]

Done.

+  // Returns true if the HQP experimenal scoring is enabled.

[Mark P, 2015/02/11 21:57:30]

spelling mistake, plus omit "the"

[Ashok vardhan, 2015/02/12 19:56:32]

Done.

+  static bool HQPExperimentalScoringEnabled();
+
+  // Returns the scoring buckets for HQP experiments. Returns empty string
+  // incase not initialized.

[Mark P, 2015/02/11 21:57:30]

1. "in case" is two words.
2. in case what is not "initialized"?  The scoring buckets?  The parameter that
defines the scoring buckets?  ...  Did you mean "defined"?
3. Any function should describe its return type.  How are "scoring buckets"
stored in a string form?  You can point people to a description elsewhere if you
want.
4. Also, I have a minor preference for returning a plausible string as the
return type if the parameter isn't defined; the empty string makes no sense.

[Ashok vardhan, 2015/02/12 19:56:32]

I dont want to return the special string if the experimental scoring is not
enabled. Hence i am returning empty string. Ideally this function is not called,
if experimental scoring is disabled.

Done.

+  static std::string HQPExperimentalScoringBuckets();
+
+  // Returns the topicality threshold for HQP experiments. If it is not
+  // initialized return -1.

[Mark P, 2015/02/11 21:57:30]

again, I think you mean:
it -> the parameter
initialized -> defined

[Ashok vardhan, 2015/02/12 19:56:31]

Done.

+  static float HQPExperimentalTopicalityThreshold();
+
+  // ---------------------------------------------------------
   // Exposed publicly for the sake of unittests.
   static const char kBundledExperimentFieldTrialName[];
   // Rule names used by the bundled experiment.
@@ -298,6 +312,11 @@ class OmniboxFieldTrial {
   static const char kHUPNewScoringVisitedCountHalfLifeTimeParam[];
   static const char kHUPNewScoringVisitedCountScoreBucketsParam[];
 
+  // Parameter names used by the HQP scoring experiments.

[Mark P, 2015/02/11 21:57:30]

insert "experimental", as you're going to do in the earlier comment

[Ashok vardhan, 2015/02/12 19:56:32]

Done.

+  static const char kHQPExperimentalScoringEnabledParam[];
+  static const char kHQPExperimentalScoringBucketsParam[];
+  static const char kHQPExperimentalScoringTopicalityThresholdParam[];
+
   // The amount of time to wait before sending a new suggest request after the
   // previous one unless overridden by a field trial parameter.
   // Non-const because some unittests modify this value.