Remove the extension QuotaService::SustainedLimit and its last client, the

extensions/browser/quota_service.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/browser/quota_service.h"
 
 #include "base/message_loop/message_loop.h"
 #include "base/stl_util.h"
 #include "extensions/browser/extension_function.h"
 #include "extensions/common/error_utils.h"
@@ skipping 119 matching lines @@
     if (!Apply(*i, event_time))
       return false;  // It only takes one to spoil it for everyone.
   }
   return true;
 }
 
 std::string QuotaLimitHeuristic::GetError() const {
   return extensions::ErrorUtils::FormatErrorMessage(kOverQuotaError, name_);
 }
 
-QuotaService::SustainedLimit::SustainedLimit(const base::TimeDelta& sustain,
-                                             const Config& config,
-                                             BucketMapper* map,
-                                             const std::string& name)
-    : QuotaLimitHeuristic(config, map, name),
-      repeat_exhaustion_allowance_(sustain.InSeconds() /
-                                   config.refill_interval.InSeconds()),
-      num_available_repeat_exhaustions_(repeat_exhaustion_allowance_) {}
-
 bool QuotaService::TimedLimit::Apply(Bucket* bucket,
                                      const base::TimeTicks& event_time) {
   if (event_time > bucket->expiration())
     bucket->Reset(config(), event_time);
 
   return bucket->DeductToken();
 }
 
-bool QuotaService::SustainedLimit::Apply(Bucket* bucket,
-                                         const base::TimeTicks& event_time) {
-  if (event_time > bucket->expiration()) {
-    // We reset state for this item and start over again if this request breaks
-    // the bad cycle that was previously being tracked.  This occurs if the
-    // state in the bucket expired recently (it has been long enough since the
-    // event that we don't care about the last event), but the bucket still has
-    // tokens (so pressure was not sustained over that time), OR we are more
-    // than 1 full refill interval away from the last event (so even if we used
-    // up all the tokens in the last bucket, nothing happened in the entire
-    // next refill interval, so it doesn't matter).
-    if (bucket->has_tokens() ||
-        event_time > bucket->expiration() + config().refill_interval) {
-      bucket->Reset(config(), event_time);
-      num_available_repeat_exhaustions_ = repeat_exhaustion_allowance_;
-    } else if (--num_available_repeat_exhaustions_ > 0) {
-      // The last interval was saturated with requests, and this is the first
-      // event in the next interval. If this happens
-      // repeat_exhaustion_allowance_ times, it's a violation. Reset the bucket
-      // state to start timing from the end of the last interval (and we'll
-      // deduct the token below) so we can detect this each time it happens.
-      bucket->Reset(config(), bucket->expiration());
-    } else {
-      // No allowances left; this request is a violation.
-      return false;
-    }
-  }
-
-  // We can go negative since we check has_tokens when we get to *next* bucket,
-  // and for the small interval all that matters is whether we used up all the
-  // tokens (which is true if num_tokens_ <= 0).
-  bucket->DeductToken();
-  return true;
-}
-
 }  // namespace extensions