Add policies to control the disk cache size.

chrome/browser/profiles/profile_impl.cc

 // Copyright (c) 2011 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 "chrome/browser/profiles/profile_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/environment.h"
@@ skipping 180 matching lines @@
   std::string value =
       CommandLine::ForCurrentProcess()->GetSwitchValueASCII(arg);
 
   // By default we let the cache determine the right size.
   *max_size = 0;
   if (!base::StringToInt(value, max_size)) {
     *max_size = 0;
   } else if (*max_size < 0) {
     *max_size = 0;
   }
+#if !defined(OS_CHROMEOS)
+  // If a policy is controlling the cache size it should override any
+  // command line flags.
+  if (kNormalContext == type) {
+    if (prefs && prefs->IsManagedPreference(prefs::kDiskCacheSize))
+      *max_size = prefs->GetInteger(prefs::kDiskCacheSize);
+  } else {
+    if (prefs && prefs->IsManagedPreference(prefs::kMediaCacheSize))
+      *max_size = prefs->GetInteger(prefs::kMediaCacheSize);
+  }

[Joao da Silva, 2011/11/15 14:12:53]

I think this policy should be user policy. The caches are stored in the profile
dir, and these policies could be used on chromeos too. It's also easier to
change in the future (e.g. to allow the user to configure the cache sizes
through some UI).

How about these changes:

1. don't read the command line here (remove the block above), and do the
equivalent logic in CommandLinePrefStore instead (it might require introducing
an IntSwitchToPreferenceMapEntry type)

2. register the prefs in the user prefs, with default value 0; this way, the
command line flags will override the default through the CommandLinePrefStore

3. the policies will override those prefs, if set;

4. in this function, just read the pref value from the profile PrefService (it
has to be passed as an argument to this function). It will either be the default
(0), the value from CommandLinePrefStore, or the policy value; in any case, it's
the right value. Also, don't wrap this reading with !OS_CHROMEOS.

+#endif
 }
 
 FilePath GetCachePath(const FilePath& base) {
   return base.Append(chrome::kCacheDirname);
 }
 
 FilePath GetMediaCachePath(const FilePath& base) {
   return base.Append(chrome::kMediaCacheDirname);
 }
 
@@ skipping 1389 matching lines @@
 void ProfileImpl::UpdateProfileUserNameCache() {
   ProfileManager* profile_manager = g_browser_process->profile_manager();
   ProfileInfoCache& cache = profile_manager->GetProfileInfoCache();
   size_t index = cache.GetIndexOfProfileWithPath(GetPath());
   if (index != std::string::npos) {
     std::string user_name =
         GetPrefs()->GetString(prefs::kGoogleServicesUsername);
     cache.SetUserNameOfProfileAtIndex(index, UTF8ToUTF16(user_name));
   }
 }