Define the storage API throttling constants in storage.json so that they are

chrome/browser/extensions/settings/settings_api.cc

Index: chrome/browser/extensions/settings/settings_api.cc
diff --git a/chrome/browser/extensions/settings/settings_api.cc b/chrome/browser/extensions/settings/settings_api.cc
index cfb749c82c07b49e98d8ff6c2f88e16753f662d0..d64409a90f2e72faf8d9c3f381efc31c23611e85 100644
--- a/chrome/browser/extensions/settings/settings_api.cc
+++ b/chrome/browser/extensions/settings/settings_api.cc
@@ -11,6 +11,7 @@
 #include "chrome/browser/extensions/settings/settings_api.h"
 #include "chrome/browser/extensions/settings/settings_frontend.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/storage.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace extensions {
@@ -118,10 +119,10 @@ std::vector<std::string> GetKeys(const DictionaryValue& dict) {
 // Creates quota heuristics for settings modification.
 static void GetModificationQuotaLimitHeuristics(
     QuotaLimitHeuristics* heuristics) {
-  // A max of 1000 operations per hour.
   QuotaLimitHeuristic::Config longLimitConfig = {
-      1000,
-      base::TimeDelta::FromHours(1)
+    // See storage.json for current value.
+    api::storage::sync::MAX_WRITE_OPERATIONS_PER_HOUR,
+    base::TimeDelta::FromHours(1)
   };
   heuristics->push_back(
       new ExtensionsQuotaService::TimedLimit(
@@ -129,8 +130,9 @@ static void GetModificationQuotaLimitHeuristics(
 
   // A max of 10 operations per minute, sustained over 10 minutes.
   QuotaLimitHeuristic::Config shortLimitConfig = {
-      10,
-      base::TimeDelta::FromMinutes(1)
+    // See storage.json for current value.
+    api::storage::sync::MAX_SUSTAINED_WRITE_OPERATIONS_PER_MINUTE,
+    base::TimeDelta::FromMinutes(1)
   };
   heuristics->push_back(
       new ExtensionsQuotaService::SustainedLimit(