Create a new Data Saver settings page that adds the site breakdown

chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc

Index: chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc
diff --git a/chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc b/chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc
index d6370f9866d02d177648dbf48995e7dbc6570047..577865841869fd9df2767b2c4f8f18ccb7541966 100644
--- a/chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc
+++ b/chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc
@@ -6,16 +6,25 @@
 
 #include <stdint.h>
 
+#include <algorithm>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
+#include "base/time/time.h"
 #include "base/values.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/pref_names.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_compression_stats.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_service.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_settings.h"
+#include "components/data_reduction_proxy/core/browser/data_usage_store.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_event_store.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.h"
@@ -29,7 +38,21 @@ using base::android::JavaParamRef;
 using base::android::ScopedJavaLocalRef;
 using data_reduction_proxy::DataReductionProxySettings;
 
-DataReductionProxySettingsAndroid::DataReductionProxySettingsAndroid() {
+namespace {
+
+const int BUCKETS_PER_DAY =

[sclittle, 2017/04/06 23:27:43]

nit: Change this to constexpr int kBucketsPerDay = ...

[megjablon, 2017/04/07 01:20:03]

Done.

+    24 * 60 / data_reduction_proxy::kDataUsageBucketLengthInMinutes;
+
+}  // namespace
+
+DataReductionProxySettingsAndroid::DataReductionProxySettingsAndroid()
+    : weak_factory_(this) {}
+
+DataReductionProxySettingsAndroid::DataReductionProxySettingsAndroid(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj)
+    : weak_factory_(this) {
+  j_settings_obj_.Reset(env, obj);
 }
 
 DataReductionProxySettingsAndroid::~DataReductionProxySettingsAndroid() {
@@ -66,6 +89,12 @@ jlong DataReductionProxySettingsAndroid::GetDataReductionLastUpdateTime(
   return Settings()->GetDataReductionLastUpdateTime();
 }
 
+void DataReductionProxySettingsAndroid::ClearDataSavingStatistics(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj) {
+  Settings()->ClearDataSavingStatistics();
+}
+
 base::android::ScopedJavaLocalRef<jobject>
 DataReductionProxySettingsAndroid::GetContentLengths(
     JNIEnv* env,
@@ -174,7 +203,82 @@ DataReductionProxySettingsAndroid::GetLastBypassEvent(
   return ConvertUTF8ToJavaString(env, event_store->SanitizedLastBypassEvent());
 }
 
+void DataReductionProxySettingsAndroid::QueryDataUsage(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& obj,
+    const JavaParamRef<jobject>& j_result_obj,
+    jint num_days) {
+  DCHECK(num_days <= data_reduction_proxy::kDataUsageHistoryNumDays);
+  j_query_result_obj_.Reset(env, j_result_obj);
+  num_day_for_query_ = num_days;
+  Settings()
+      ->data_reduction_proxy_service()
+      ->compression_stats()
+      ->GetHistoricalDataUsage(base::Bind(
+          &DataReductionProxySettingsAndroid::OnQueryDataUsageComplete,
+          weak_factory_.GetWeakPtr()));
+}
+
+void DataReductionProxySettingsAndroid::OnQueryDataUsageComplete(
+    std::unique_ptr<std::vector<data_reduction_proxy::DataUsageBucket>>
+        data_usage) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+
+  int data_usage_size = data_usage->size();
+  int num_buckets_to_display =
+      std::min(num_day_for_query_ * BUCKETS_PER_DAY, data_usage_size);
+
+  std::unordered_map<std::string, std::unique_ptr<base::DictionaryValue>>

[sclittle, 2017/04/06 23:27:43]

Instead of using DictionaryValue here, you could just define a struct in the
anonymous namespace above, e.g. something like:

struct DataUsageForHost {
  DataUsageForHost() : data_used(0), original_size(0) {}

  int64_t data_used;
  int64_t original_size;
};

Then, you could just have a std::map<base::StringPiece, DataUsageForHost>
per_site_usage_map; and replace the body of the innermost for-loop below with:

for (const auto& site_usage : connection_usage.site_usage()) {
  DataUsageForHost& usage =
      per_site_usage_map[site_usage.hostname()];
  usage.data_usage += site_usage.data_used();
  usage.original_size += site_usage.original_size();
}

[megjablon, 2017/04/07 01:20:03]

Done.

+      per_site_usage_map;
+
+  // Data usage is sorted chronologically with the last entry corresponding to
+  // |base::Time::Now()|.
+  for (int i = data_usage_size - 1;

[sclittle, 2017/04/06 23:27:43]

Using signed ints for indices like this seems a bit sketchy, could you replace
this with something like:

const size_t num_buckets_to_display =
    num_day_for_query_ * kBucketsPerDay;
for (auto data_usage_it =
         data_usage->size() > num_buckets_to_display
             ? data_usage->end() - num_buckets_to_display
             : data_usage->begin();
     data_usage_it != data_usage->end(); ++data_usage_it) {

  // ... inner for loops ...

}

[megjablon, 2017/04/07 01:20:03]

Done.

+       i >= data_usage_size - num_buckets_to_display; i--) {
+    const auto& data_usage_bucket = data_usage->at(i);
+    for (const auto& connection_usage : data_usage_bucket.connection_usage()) {
+      for (const auto& site_usage : connection_usage.site_usage()) {
+        auto usage = per_site_usage_map.find(site_usage.hostname());
+        if (usage != per_site_usage_map.end()) {
+          double data_used;
+          double original_size;
+          usage->second->GetDouble("data_used", &data_used);

[sclittle, 2017/04/06 23:27:43]

Why are these doubles? Could they just be int64s?

[megjablon, 2017/04/07 01:20:02]

This is obsolete.

+          usage->second->GetDouble("original_size", &original_size);
+          usage->second->SetDouble("data_used",
+                                   data_used + site_usage.data_used());
+          usage->second->SetDouble("original_size",
+                                   original_size + site_usage.original_size());
+        } else {
+          std::unique_ptr<base::DictionaryValue> usageValue =
+              base::MakeUnique<base::DictionaryValue>();
+          usageValue->SetDouble("data_used", site_usage.data_used());
+          usageValue->SetDouble("original_size", site_usage.original_size());
+          per_site_usage_map.insert(
+              std::make_pair(site_usage.hostname(), std::move(usageValue)));
+        }
+      }
+    }
+  }
+
+  for (const auto& site_bucket : per_site_usage_map) {
+    double data_used;
+    double original_size;
+    site_bucket.second->GetDouble("data_used", &data_used);
+    site_bucket.second->GetDouble("original_size", &original_size);
+    Java_DataReductionProxySettings_createDataUseItemAndAddToList(

[sclittle, 2017/04/06 23:27:43]

Instead of adding the items one-by-one making a jni-call for each hostname, is
there some way you could send them all over at once in a single batch?

[megjablon, 2017/04/07 01:20:02]

I don't know of a way. I followed the same pattern as we use to get history
items and create a list:

https://cs.chromium.org/chromium/src/chrome/browser/android/history/browsing_...

+        env, j_query_result_obj_.obj(),
+        ConvertUTF8ToJavaString(env, site_bucket.first), (long)data_used,
+        (long)original_size);
+  }
+
+  Java_DataReductionProxySettings_onQueryDataUsageComplete(
+      env, j_settings_obj_.obj(), j_query_result_obj_.obj());
+
+  j_query_result_obj_.Release();
+}
+
 // Used by generated jni code.
 static jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
-  return reinterpret_cast<intptr_t>(new DataReductionProxySettingsAndroid());
+  return reinterpret_cast<intptr_t>(
+      new DataReductionProxySettingsAndroid(env, obj));
 }