Only register the newer one of {bundled, component} Pepper Flash.

chrome/browser/component_updater/pepper_flash_component_installer.cc

 // Copyright (c) 2012 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/component_updater/flash_component_installer.h"
 
 #include <string.h>
 
 #include <vector>
 
 #include "base/base_paths.h"
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
+#include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "base/version.h"
 #include "build/build_config.h"
 #include "chrome/browser/component_updater/component_updater_service.h"
 #include "chrome/browser/plugins/plugin_prefs.h"
 #include "chrome/common/pepper_flash.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/pepper_flash.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 125 matching lines @@
                                           kFlashPluginSwfExtension,
                                           kFlashPluginName);
   plugin_info->mime_types.push_back(swf_mime_type);
   webkit::WebPluginMimeType spl_mime_type(kFlashPluginSplMimeType,
                                           kFlashPluginSplExtension,
                                           kFlashPluginName);
   plugin_info->mime_types.push_back(spl_mime_type);
   return true;
 }
 
+bool IsPepperFlash(const webkit::WebPluginInfo& plugin) {
+  return webkit::IsPepperPlugin(plugin) &&
+         (plugin.pepper_permissions & ppapi::PERMISSION_FLASH);

[cpu_(ooo_6.6-7.5), 2012/10/09 20:00:36]

can you add a comment here about this check. I am unfamiliar with this
permission thing.

[Bernhard Bauer, 2012/10/09 20:52:40]

Will do. I could also use a different criterion to look for Pepper Flash, but
this seems like the most stable one. 

+}
+
 void RegisterPepperFlashWithChrome(const FilePath& path,
                                    const Version& version) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   content::PepperPluginInfo plugin_info;
   if (!MakePepperFlashPluginInfo(path, version, true, &plugin_info))
     return;
+
+  std::vector<webkit::WebPluginInfo> plugins;
+  PluginService::GetInstance()->GetInternalPlugins(&plugins);
+  for (std::vector<webkit::WebPluginInfo>::const_iterator it = plugins.begin();
+       it != plugins.end(); ++it) {
+    if (!IsPepperFlash(*it))
+      continue;

[cpu_(ooo_6.6-7.5), 2012/10/09 20:00:36]

is this doing IO? do we want to call this instead from line 333 ? 

I assume that the caller of line 258 is not the issue. Is it?

[Bernhard Bauer, 2012/10/09 20:52:40]

No, it just asks PluginList for its internal plugins (for which we don't need to
hit the disk) and then looks at the returned structs.
Not in this particular manifestation of the bug, but seeing as we have two
completely independent channels here to deploy Flapper, I just wanted to make
sure we do The Right Thing in every case, which is only loading the newer
plugin.

+
+    // If the version we're trying to register is older than the existing one,
+    // don't do it.
+    if (version.IsOlderThan(UTF16ToUTF8(it->version)))
+      return;
+
+    // If the version is newer, remove the old one first.
+    PluginService::GetInstance()->UnregisterInternalPlugin(it->path);
+    break;
+  }
+
   bool add_to_front = IsPepperFlashEnabledByDefault();
   PluginService::GetInstance()->RegisterInternalPlugin(
       plugin_info.ToWebPluginInfo(), add_to_front);
   PluginService::GetInstance()->RefreshPlugins();
 }
 
 // Returns true if this browser implements one of the interfaces given in
 // |interface_string|, which is a '|'-separated string of interface names.
 bool CheckPepperFlashInterfaceString(const std::string& interface_string) {
   std::vector<std::string> interface_names;
@@ skipping 170 matching lines @@
 #endif  // defined(GOOGLE_CHROME_BUILD)
 
 }  // namespace
 
 void RegisterPepperFlashComponent(ComponentUpdateService* cus) {
 #if defined(GOOGLE_CHROME_BUILD)
   BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
                           base::Bind(&StartPepperFlashUpdateRegistration, cus));
 #endif
 }