Fix AmountOfFreeDiskSpace to be able to differentiate an error...

net/disk_cache/mem_backend_impl.cc

 // Copyright (c) 2006-2008 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 "net/disk_cache/mem_backend_impl.h"
 
 #include "base/sys_info.h"
 #include "net/disk_cache/cache_util.h"
 #include "net/disk_cache/mem_entry_impl.h"
 
@@ skipping 25 matching lines @@
 }
 
 // ------------------------------------------------------------------------
 
 bool MemBackendImpl::Init() {
   if (max_size_)
     return true;
 
   int64 total_memory = base::SysInfo::AmountOfPhysicalMemory();
 
-  if (total_memory < 0) {
+  if (total_memory <= 0) {
     max_size_ = kDefaultCacheSize;
     return true;
   }
 
   // We want to use up to 2% of the computer's memory, with a limit of 50 MB,
   // reached on systemd with more than 2.5 GB of RAM.
   total_memory = total_memory * 2 / 100;
   if (total_memory > kDefaultCacheSize * 5)
     max_size_ = kDefaultCacheSize * 5;
   else
@@ skipping 187 matching lines @@
 void MemBackendImpl::UpdateRank(MemEntryImpl* node) {
   rankings_.UpdateRank(node);
 }
 
 int MemBackendImpl::MaxFileSize() const {
   return max_size_ / 8;
 }
 
 }  // namespace disk_cache