Enforce the 'requirements' field in manifests.

chrome/browser/extensions/extension_service.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/extensions/extension_service.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/basictypes.h"
@@ skipping 2109 matching lines @@
     if (!extension->is_theme() && extension->location() != Extension::COMPONENT)
       extension_ids.insert(extension->id());
   }
 
   child_process_logging::SetActiveExtensions(extension_ids);
 }
 
 void ExtensionService::OnExtensionInstalled(
     const Extension* extension,
     bool from_webstore,
-    const syncer::StringOrdinal& page_ordinal) {
+    const syncer::StringOrdinal& page_ordinal,
+    bool has_requirement_errors) {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // Ensure extension is deleted unless we transfer ownership.
   scoped_refptr<const Extension> scoped_extension(extension);
   const std::string& id = extension->id();
   // Extensions installed by policy can't be disabled. So even if a previous
   // installation disabled the extension, make sure it is now enabled.
   bool initial_enable =
       !extension_prefs_->IsExtensionDisabled(id) ||
       system_->management_policy()->MustRemainEnabled(extension, NULL);
@@ skipping 26 matching lines @@
     pending_extension_manager()->Remove(id);
   } else {
     // We explicitly want to re-enable an uninstalled external
     // extension; if we're here, that means the user is manually
     // installing the extension.
     if (IsExternalExtensionUninstalled(id)) {
       initial_enable = true;
     }
   }
 
+  // Unsupported requirements overrides the management policy.
+  if (has_requirement_errors) {
+    initial_enable = false;
+    extension_prefs_->AddDisableReason(
+        id, Extension::DISABLE_UNSUPPORTED_REQUIREMENT);
+  // If the extension was disabled because of unsupported requirements but
+  // now supports all requirements after an update and there are not other
+  // disable reasons, enable it.
+  } else if (extension_prefs_->GetDisableReasons(id) ==
+      Extension::DISABLE_UNSUPPORTED_REQUIREMENT) {
+    initial_enable = true;
+    extension_prefs_->ClearDisableReasons(id);
+  }
+
   int include_mask = INCLUDE_ENABLED;
   include_mask |= INCLUDE_DISABLED;
   // Do not record the install histograms for upgrades.
   if (!GetExtensionByIdInternal(extension->id(), include_mask)) {
     UMA_HISTOGRAM_ENUMERATION("Extensions.InstallType",
                               extension->GetType(), 100);
     RecordPermissionMessagesHistogram(
         extension, "Extensions.Permissions_Install");
   }
 
@@ skipping 437 matching lines @@
     extensions::ExtensionHost* extension_host) {
   if (!extension_host)
     return;
 
 #if !defined(OS_ANDROID)
   extensions::LaunchPlatformApp(extension_host->profile(),
                                 extension_host->extension(),
                                 NULL, FilePath());
 #endif
 }