Record to UMA when a durable origin is passed over for eviction.

BUG=521075

Review URL: https://codereview.chromium.org/1305383002

Cr-Commit-Position: refs/heads/master@{#345798}

storage/browser/quota/quota_database.cc

@@ -9,6 +9,7 @@
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/files/file_util.h"
+#include "base/metrics/histogram_macros.h"
 #include "sql/connection.h"
 #include "sql/meta_table.h"
 #include "sql/statement.h"
@@ -35,6 +36,24 @@ bool VerifyValidQuotaConfig(const char* key) {
 
 const int kCommitIntervalMs = 30000;
 
+enum OriginType {
+  // This enum is logged to UMA so only append to it - don't change
+  // the meaning of the existing values.
+  OTHER = 0,
+  NONE = 1,
+  GOOGLE_DURABLE = 2,
+  NON_GOOGLE_DURABLE = 3,
+  GOOGLE_UNLIMITED_EXTENSION = 4,
+  NON_GOOGLE_UNLIMITED_EXTENSION = 5,
+  IN_USE = 6,
+
+  MAX_ORIGIN_TYPE
+};
+
+void HistogramOriginType(const OriginType& entry) {
+  UMA_HISTOGRAM_ENUMERATION("Quota.LRUOriginTypes", entry, MAX_ORIGIN_TYPE);
+}
+
 }  // anonymous namespace
 
 // static
@@ -340,16 +359,28 @@ bool QuotaDatabase::GetLRUOrigin(
 
   while (statement.Step()) {
     GURL url(statement.ColumnString(0));
-    if (exceptions.find(url) != exceptions.end())
-      continue;
-    if (special_storage_policy &&
-        (special_storage_policy->IsStorageDurable(url) ||
-         special_storage_policy->IsStorageUnlimited(url)))
+    if (exceptions.find(url) != exceptions.end()) {
+      HistogramOriginType(IN_USE);
       continue;
+    }
+    if (special_storage_policy) {
+      bool is_google = url.DomainIs("google.com");
+      if (special_storage_policy->IsStorageDurable(url)) {
+        HistogramOriginType(is_google ? GOOGLE_DURABLE : NON_GOOGLE_DURABLE);
+        continue;
+      }
+      if (special_storage_policy->IsStorageUnlimited(url)) {
+        HistogramOriginType(is_google ? GOOGLE_UNLIMITED_EXTENSION
+                                      : NON_GOOGLE_UNLIMITED_EXTENSION);
+        continue;
+      }
+    }
+    HistogramOriginType(OTHER);
     *origin = url;
     return true;
   }
 
+  HistogramOriginType(NONE);
   *origin = GURL();
   return statement.Succeeded();
 }

tools/metrics/histograms/histograms.xml

@@ -35253,6 +35253,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>Initial quota for global temporary storage.</summary>
 </histogram>
 
+<histogram name="Quota.LRUOriginTypes" enum="QuotaOriginTypes">
+  <owner>[email protected]</owner>
+  <summary>
+    Types of origins that are initially selected for eviction via LRU. Some of
+    these types are exempt from eviction.
+  </summary>
+</histogram>
+
 <histogram name="Quota.NumberOfEvictedOriginsPerRound">
   <owner>[email protected]</owner>
   <summary>Number of evicted origins per round.</summary>
@@ -69059,6 +69067,16 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="5" label="NOTIFY_FACTORY_OF_SESSION_CLOSED"/>
 </enum>
 
+<enum name="QuotaOriginTypes" type="int">
+  <int value="0" label="Other"/>
+  <int value="1" label="None"/>
+  <int value="2" label="google.com durable"/>
+  <int value="3" label="non-google.com durable"/>
+  <int value="4" label="google.com unlimitedStorage app/ext"/>
+  <int value="5" label="non-google.com unlimitedStorage app/ext"/>
+  <int value="6" label="In use"/>
+</enum>
+
 <enum name="RapporDiscardReason" type="int">
   <int value="0" label="Upload Success"/>
   <int value="1" label="Upload Rejected"/>