Remove all traces of pref hash stores after last store reset.

chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc

Index: chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc
diff --git a/chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc b/chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc
index 789fd1a24a27bae5bfbea88d1f6040f2cdd9bbf1..324a5a0c69f710b14827a6bae3ea060d06e1ec28 100644
--- a/chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc
+++ b/chrome/browser/prefs/tracked/pref_service_hash_store_contents_unittest.cc
@@ -9,6 +9,7 @@
 #include "base/prefs/pref_service.h"
 #include "base/prefs/testing_pref_service.h"
 #include "base/values.h"
+#include "chrome/common/pref_names.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 class PrefServiceHashStoreContentsTest : public testing::Test {
@@ -43,6 +44,8 @@ TEST_F(PrefServiceHashStoreContentsTest, IsInitialized) {
 }
 
 TEST_F(PrefServiceHashStoreContentsTest, Reset) {
+  ASSERT_FALSE(local_state_.GetUserPrefValue(prefs::kProfilePreferenceHashes));
+
   {
     PrefServiceHashStoreContents contents("store_id", &local_state_);
     ASSERT_FALSE(contents.IsInitialized());
@@ -53,12 +56,18 @@ TEST_F(PrefServiceHashStoreContentsTest, Reset) {
     (*other_contents.GetMutableContents())
         ->Set("foo", new base::StringValue("bar"));
   }
+
+  ASSERT_TRUE(local_state_.GetUserPrefValue(prefs::kProfilePreferenceHashes));
+
   {
     PrefServiceHashStoreContents contents("store_id", &local_state_);
     ASSERT_TRUE(contents.IsInitialized());
     contents.Reset();
     ASSERT_FALSE(contents.IsInitialized());
   }
+
+  ASSERT_TRUE(local_state_.GetUserPrefValue(prefs::kProfilePreferenceHashes));
+
   {
     PrefServiceHashStoreContents contents("store_id", &local_state_);
     ASSERT_FALSE(contents.IsInitialized());
@@ -66,6 +75,14 @@ TEST_F(PrefServiceHashStoreContentsTest, Reset) {
                                                 &local_state_);
     ASSERT_TRUE(other_contents.IsInitialized());
   }
+
+  {
+    PrefServiceHashStoreContents other_contents("other_store_id",
+                                                &local_state_);
+    other_contents.Reset();
+  }
+
+  ASSERT_FALSE(local_state_.GetUserPrefValue(prefs::kProfilePreferenceHashes));
 }
 
 TEST_F(PrefServiceHashStoreContentsTest, GetAndSetContents) {