Adding DRP specfic UMA for FirstContentfulPaint

chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc

Index: chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc
diff --git a/chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc b/chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc
index de5dbfee5ba789709a29d469ddc0a744d3f6172e..71a6ae9683140c3353bd939f0aaf0834444db7b9 100644
--- a/chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc
+++ b/chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc
@@ -2,20 +2,21 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
 #include "chrome/browser/browser_process.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/page_load_metrics/browser/page_load_metrics_util.h"
 #include "components/rappor/rappor_service.h"
 #include "components/rappor/rappor_utils.h"
 
 namespace {
 
 // The number of buckets in the bitfield histogram. These buckets are described
 // in rappor.xml in PageLoad.CoarseTiming.NavigationToFirstContentfulPaint.
 // The bucket flag is defined by 1 << bucket_index, and is the bitfield
 // representing which timing bucket the page load falls into, i.e. 000010
@@ -84,20 +85,28 @@ const char kHistogramFirstForeground[] =
 const char kHistogramBackgroundBeforePaint[] =
     "PageLoad.Timing2.NavigationToFirstBackground.AfterCommit.BeforePaint";
 const char kHistogramBackgroundBeforeCommit[] =
     "PageLoad.Timing2.NavigationToFirstBackground.BeforeCommit";
 const char kHistogramFailedProvisionalLoad[] =
     "PageLoad.Timing2.NavigationToFailedProvisionalLoad";
 
 const char kRapporMetricsNameCoarseTiming[] =
     "PageLoad.CoarseTiming.NavigationToFirstContentfulPaint";
 
+const char kHistogramFirstContentfulPaintDataReductionProxy[] =
+    "PageLoad.Timing2.NavigationToFirstContentfulPaint_DataReductionProxy";
+const char kHistogramFirstContentfulPaintDataReductionProxyAutoLofiOn[] =
+    "PageLoad.Timing2.NavigationToFirstContentfulPaint_DataReductionProxy_"
+    "AutoLoFiOn";
+const char kHistogramFirstContentfulPaintDataReductionProxyAutoLofiOff[] =
+    "PageLoad.Timing2.NavigationToFirstContentfulPaint_DataReductionProxy_"
+    "AutoLofiOff";
 }  // namespace internal
 
 CorePageLoadMetricsObserver::CorePageLoadMetricsObserver() {}
 
 CorePageLoadMetricsObserver::~CorePageLoadMetricsObserver() {}
 
 void CorePageLoadMetricsObserver::OnComplete(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
   RecordTimingHistograms(timing, info);
@@ -218,20 +227,42 @@ void CorePageLoadMetricsObserver::RecordTimingHistograms(
         PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstContentfulPaintHigh,
                             timing.first_contentful_paint);
       } else {
         PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstContentfulPaintLow,
                             timing.first_contentful_paint);
       }
     } else {
       PAGE_LOAD_HISTOGRAM(internal::kBackgroundHistogramFirstContentfulPaint,
                           timing.first_contentful_paint);
     }
+    if (info.was_fetched_via_data_reduction_proxy) {
+      PAGE_LOAD_HISTOGRAM(
+          internal::kHistogramFirstContentfulPaintDataReductionProxy,
+          timing.first_contentful_paint);
+      if (info.is_using_lofi) {
+        bool in_lofi_enabled_group =

[bengr, 2016/02/26 22:53:57]

I'd get rid of these temporaries.

[RyanSturm, 2016/03/01 19:36:03]

Done.

+            data_reduction_proxy::params::IsIncludedInLoFiEnabledFieldTrial();
+        bool in_lofi_control_group =
+            data_reduction_proxy::params::IsIncludedInLoFiControlFieldTrial();
+        if (in_lofi_enabled_group) {
+          PAGE_LOAD_HISTOGRAM(
+              internal::
+                  kHistogramFirstContentfulPaintDataReductionProxyAutoLofiOn,
+              timing.first_contentful_paint);
+        } else if (in_lofi_control_group) {
+          PAGE_LOAD_HISTOGRAM(
+              internal::
+                  kHistogramFirstContentfulPaintDataReductionProxyAutoLofiOff,
+              timing.first_contentful_paint);
+        }
+      }
+    }
   }
 
   // Log time to first foreground / time to first background. Log counts that we
   // started a relevant page load in the foreground / background.
   if (!info.first_background_time.is_zero())
     PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstBackground,
                         info.first_background_time);
   else if (!info.first_foreground_time.is_zero())
     PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstForeground,
                         info.first_foreground_time);