Enforce the 'requirements' field in manifests.

chrome/browser/extensions/crx_installer.cc

Index: chrome/browser/extensions/crx_installer.cc
diff --git a/chrome/browser/extensions/crx_installer.cc b/chrome/browser/extensions/crx_installer.cc
index dcb1046cfc7d58fc4488769287b85110b2fe3f74..82658727e6db0eff74a226717deda9d85189c1c1 100644
--- a/chrome/browser/extensions/crx_installer.cc
+++ b/chrome/browser/extensions/crx_installer.cc
@@ -16,6 +16,7 @@
 #include "base/scoped_temp_dir.h"
 #include "base/stl_util.h"
 #include "base/stringprintf.h"
+#include "base/string_util.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
@@ -29,6 +30,7 @@
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/permissions_updater.h"
+#include "chrome/browser/extensions/requirements_checker.h"
 #include "chrome/browser/extensions/webstore_installer.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/shell_integration.h"
@@ -101,7 +103,9 @@ CrxInstaller::CrxInstaller(
       creation_flags_(Extension::NO_FLAGS),
       off_store_install_allow_reason_(OffStoreInstallDisallowed),
       did_handle_successfully_(true),
-      record_oauth2_grant_(false) {
+      record_oauth2_grant_(false),
+      error_on_unsupported_requirements_(false),
+      requirements_checker_(new extensions::RequirementsChecker()) {
   if (!approval)
     return;
 
@@ -204,7 +208,7 @@ void CrxInstaller::ConvertWebAppOnFileThread(
   OnUnpackSuccess(extension->path(), extension->path(), NULL, extension);
 }
 
-CrxInstallerError CrxInstaller::AllowInstall(const Extension* extension) {
+CrxInstallerError CrxInstaller::AllowInstall(Extension* extension) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
   // Make sure the expected ID matches if one was supplied or if we want to
@@ -349,7 +353,7 @@ void CrxInstaller::OnUnpackFailure(const string16& error_message) {
 void CrxInstaller::OnUnpackSuccess(const FilePath& temp_dir,
                                    const FilePath& extension_dir,
                                    const DictionaryValue* original_manifest,
-                                   const Extension* extension) {
+                                   Extension* extension) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
   UMA_HISTOGRAM_ENUMERATION("Extensions.UnpackSuccessInstallSource",
@@ -384,10 +388,30 @@ void CrxInstaller::OnUnpackSuccess(const FilePath& temp_dir,
                           &install_icon_);
   }
 
-  if (!BrowserThread::PostTask(
-          BrowserThread::UI, FROM_HERE,
-          base::Bind(&CrxInstaller::ConfirmInstall, this)))
-    NOTREACHED();
+  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+      base::Bind(&CrxInstaller::CheckRequirements, this));
+}
+
+void CrxInstaller::CheckRequirements() {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  requirements_checker_->Check(extension_,
+                               base::Bind(&CrxInstaller::RequirementsChecked,
+                                          this));
+}
+
+void CrxInstaller::RequirementsChecked(std::vector<std::string> errors) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  if (!errors.empty()) {
+    if (error_on_unsupported_requirements_) {
+      ReportFailureFromUIThread(CrxInstallerError(
+          UTF8ToUTF16(JoinString(errors, ' '))));
+      return;
+    }
+    requirement_errors_.swap(errors);
+  }
+
+  ConfirmInstall();
 }
 
 void CrxInstaller::ConfirmInstall() {
@@ -520,6 +544,17 @@ void CrxInstaller::CompleteInstall() {
       &error);
   CHECK(error.empty()) << error;
 
+  if (!requirement_errors_.empty()) {
+    extensions::Extension::InstallWarningVector install_warnings;
+    for (std::vector<std::string>::iterator it = requirement_errors_.begin();
+         it != requirement_errors_.end();
+         ++it) {
+      install_warnings.push_back(Extension::InstallWarning(
+          Extension::InstallWarning::FORMAT_TEXT, *it));
+    }
+    extension_->AddInstallWarnings(install_warnings);
+  }
+
   ReportSuccessFromFileThread();
 }
 
@@ -602,8 +637,10 @@ void CrxInstaller::ReportSuccessFromUIThread() {
 
   // Tell the frontend about the installation and hand off ownership of
   // extension_ to it.
-  frontend_weak_->OnExtensionInstalled(extension_, is_gallery_install(),
-                                       page_ordinal_);
+  frontend_weak_->OnExtensionInstalled(extension_,
+                                       is_gallery_install(),
+                                       page_ordinal_,
+                                       requirement_errors_);
 
   NotifyCrxInstallComplete(extension_.get());
 
@@ -613,7 +650,7 @@ void CrxInstaller::ReportSuccessFromUIThread() {
   // soon.
 }
 
-void CrxInstaller::NotifyCrxInstallComplete(const Extension* extension) {
+void CrxInstaller::NotifyCrxInstallComplete(Extension* extension) {
   // Some users (such as the download shelf) need to know when a
   // CRXInstaller is done.  Listening for the EXTENSION_* events
   // is problematic because they don't know anything about the