Remove some unused LoFi histograms

Bug: 823569
Change-Id: If226bd56a981e78aa2fe9da89e144b930a064502
Reviewed-on: https://chromium-review.googlesource.com/991074Reviewed-by: Mark Pearson <mpearson@chromium.org>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Robert Ogden <robertogden@google.com>
Cr-Commit-Position: refs/heads/master@{#547841}

components/data_reduction_proxy/content/browser/content_lofi_decider.cc

@@ -59,15 +59,6 @@ ContentLoFiDecider::DetermineCommittedServerPreviewsState(
   return updated_state;
 }
 
-bool ContentLoFiDecider::IsUsingLoFi(const net::URLRequest& request) const {
-  const content::ResourceRequestInfo* request_info =
-      content::ResourceRequestInfo::ForRequest(&request);
-  if (!request_info)
-    return false;
-
-  return (request_info->GetPreviewsState() & content::SERVER_LOFI_ON);
-}
-
 void ContentLoFiDecider::MaybeSetAcceptTransformHeader(
     const net::URLRequest& request,
     net::HttpRequestHeaders* headers) const {

components/data_reduction_proxy/content/browser/content_lofi_decider.h

@@ -44,7 +44,6 @@ class ContentLoFiDecider : public LoFiDecider {
       content::PreviewsState initial_state);
 
   // LoFiDecider implementation:
-  bool IsUsingLoFi(const net::URLRequest& request) const override;
   void MaybeSetAcceptTransformHeader(
       const net::URLRequest& request,
       net::HttpRequestHeaders* headers) const override;

components/data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate.cc

@@ -112,14 +112,11 @@ void RecordNewContentLengthHistograms(
   }
 }
 
-// |lofi_low_header_added| is set to true iff Lo-Fi request header
-// can be added to the Chrome proxy header. |received_content_length| is
-// the number of prefilter bytes received. |original_content_length| is the
-// length of resource if accessed directly without data saver proxy.
-// |freshness_lifetime| specifies how long the resource will
-// be fresh for.
-void RecordContentLengthHistograms(bool lofi_low_header_added,
-                                   bool is_https,
+// |received_content_length| is the number of prefilter bytes received.
+// |original_content_length| is the length of resource if accessed directly
+// without data saver proxy. |freshness_lifetime| specifies how long the
+// resource will be fresh for.
+void RecordContentLengthHistograms(bool is_https,
                                    bool is_video,
                                    int64_t received_content_length,
                                    int64_t original_content_length,
@@ -134,19 +131,6 @@ void RecordContentLengthHistograms(bool lofi_low_header_added,
                             original_content_length);
     UMA_HISTOGRAM_COUNTS_1M("Net.HttpContentLengthDifferenceWithValidOCL",
                             original_content_length - received_content_length);
-
-    // Populate Lo-Fi content length histograms.
-    if (lofi_low_header_added) {
-      UMA_HISTOGRAM_COUNTS_1M("Net.HttpContentLengthWithValidOCL.LoFiOn",
-                              received_content_length);
-      UMA_HISTOGRAM_COUNTS_1M(
-          "Net.HttpOriginalContentLengthWithValidOCL.LoFiOn",
-          original_content_length);
-      UMA_HISTOGRAM_COUNTS_1M(
-          "Net.HttpContentLengthDifferenceWithValidOCL.LoFiOn",
-          original_content_length - received_content_length);
-    }
-
   } else {
     // Presume the original content length is the same as the received content
     // length.
@@ -640,11 +624,6 @@ void DataReductionProxyNetworkDelegate::RecordContentLength(
   }
 
   RecordContentLengthHistograms(
-      // |data_reduction_proxy_io_data_| can be NULL for Webview.
-      data_reduction_proxy_io_data_ &&
-          data_reduction_proxy_io_data_->IsEnabled() &&
-          data_reduction_proxy_io_data_->lofi_decider() &&
-          data_reduction_proxy_io_data_->lofi_decider()->IsUsingLoFi(request),
       is_https, is_video, request.received_response_content_length(),
       original_content_length, freshness_lifetime, request_type);
 

components/data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate_unittest.cc

@@ -127,14 +127,6 @@ const char kOriginalVideoSecureBypassedHistogramName[] =
 const char kOriginalVideoSecureOtherHistogramName[] =
     "Net.HttpOriginalContentLengthV2.Https.Other.Video";
 
-// Lo-Fi histograms.
-const char kReceivedValidOCLLoFiOnHistogramName[] =
-    "Net.HttpContentLengthWithValidOCL.LoFiOn";
-const char kOriginalValidOCLLoFiOnHistogramName[] =
-    "Net.HttpOriginalContentLengthWithValidOCL.LoFiOn";
-const char kDifferenceValidOCLLoFiOnHistogramName[] =
-    "Net.HttpContentLengthDifferenceWithValidOCL.LoFiOn";
-
 const char kReceivedHistogramName[] = "Net.HttpContentLength";
 const char kReceivedInsecureDirectHistogramName[] =
     "Net.HttpContentLengthV2.Http.Direct";
@@ -213,10 +205,6 @@ class TestLoFiDecider : public LoFiDecider {
         ignore_is_using_data_reduction_proxy_check_(false) {}
   ~TestLoFiDecider() override {}
 
-  bool IsUsingLoFi(const net::URLRequest& request) const override {
-    return should_request_lofi_resource_;
-  }
-
   void SetIsUsingLoFi(bool should_request_lofi_resource) {
     should_request_lofi_resource_ = should_request_lofi_resource;
   }
@@ -1285,67 +1273,6 @@ TEST_F(DataReductionProxyNetworkDelegateTest, NetHistograms) {
                                       kResponseContentLength, 1);
   histogram_tester.ExpectUniqueSample(kCacheable24HoursHistogramName,
                                       kResponseContentLength, 1);
-
-  // Check Lo-Fi histograms.
-  const struct {
-    bool lofi_enabled;
-    int expected_count;
-  } tests[] = {
-      {
-          // Lo-Fi disabled.
-          false, 0,
-      },
-      {
-          // Lo-Fi enabled so should populate Lo-Fi content length histogram.
-          true, 1,
-      },
-  };
-
-  for (size_t i = 0; i < arraysize(tests); ++i) {
-
-    base::test::ScopedFeatureList scoped_feature_list;
-    if (tests[i].lofi_enabled) {
-      scoped_feature_list.InitAndEnableFeature(
-          features::kDataReductionProxyDecidesTransform);
-    } else {
-      scoped_feature_list.InitAndDisableFeature(
-          features::kDataReductionProxyDecidesTransform);
-    }
-
-    // Needed as a parameter, but functionality is not tested.
-    previews::TestPreviewsDecider test_previews_decider(true);
-    lofi_decider()->SetIsUsingLoFi(config()->ShouldAcceptServerPreview(
-        *fake_request.get(), test_previews_decider));
-
-    fake_request = (FetchURLRequest(GURL(kTestURL), nullptr, response_headers,
-                                    kResponseContentLength, 0));
-    fake_request->SetLoadFlags(fake_request->load_flags() |
-                               net::LOAD_MAIN_FRAME_DEPRECATED);
-
-    // Histograms are accumulative, so get the sum of all the tests so far.
-    int expected_count = 0;
-    for (size_t j = 0; j <= i; ++j)
-      expected_count += tests[j].expected_count;
-
-    if (expected_count == 0) {
-      histogram_tester.ExpectTotalCount(kReceivedValidOCLLoFiOnHistogramName,
-                                        expected_count);
-      histogram_tester.ExpectTotalCount(kOriginalValidOCLLoFiOnHistogramName,
-                                        expected_count);
-      histogram_tester.ExpectTotalCount(kDifferenceValidOCLLoFiOnHistogramName,
-                                        expected_count);
-    } else {
-      histogram_tester.ExpectUniqueSample(kReceivedValidOCLLoFiOnHistogramName,
-                                          kResponseContentLength,
-                                          expected_count);
-      histogram_tester.ExpectUniqueSample(kOriginalValidOCLLoFiOnHistogramName,
-                                          kOriginalContentLength,
-                                          expected_count);
-      histogram_tester.ExpectUniqueSample(
-          kDifferenceValidOCLLoFiOnHistogramName,
-          kOriginalContentLength - kResponseContentLength, expected_count);
-    }
-  }
 }
 
 TEST_F(DataReductionProxyNetworkDelegateTest, NetVideoHistograms) {

components/data_reduction_proxy/core/common/lofi_decider.h

@@ -26,10 +26,6 @@ class LoFiDecider {
  public:
   virtual ~LoFiDecider() {}
 
-  // Returns true when Lo-Fi Previews are on for the given |request|. This means
-  // the Lo-Fi header should be added to the given request.
-  virtual bool IsUsingLoFi(const net::URLRequest& request) const = 0;
-
   // Adds a previews-specific directive to the Chrome-Proxy-Accept-Transform
   // header if needed.
   virtual void MaybeSetAcceptTransformHeader(

tools/metrics/histograms/histograms.xml

@@ -106846,6 +106846,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram_suffixes>
 
 <histogram_suffixes name="DataReductionProxy.WithValidOCL.LoFiOn" separator=".">
+  <obsolete>
+    Deprecated 04/2018.
+  </obsolete>
   <suffix name="LoFiOn"
       label="Only page loads through the data reduction proxy with Lo-Fi On
              are considered."/>