Extensions: Prepare switch to new permission message system

chrome/common/extensions/permissions/chrome_permission_message_provider.cc

Index: chrome/common/extensions/permissions/chrome_permission_message_provider.cc
diff --git a/chrome/common/extensions/permissions/chrome_permission_message_provider.cc b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
index d5ceeea6ba28f1041750247c2095a1fcdd7061f6..0ed371e7c69f4ede0e834912089baa19d4de551a 100644
--- a/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
+++ b/chrome/common/extensions/permissions/chrome_permission_message_provider.cc
@@ -5,6 +5,7 @@
 #include "chrome/common/extensions/permissions/chrome_permission_message_provider.h"
 
 #include "base/memory/scoped_vector.h"
+#include "base/metrics/field_trial.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
@@ -24,6 +25,12 @@ namespace extensions {
 
 namespace {
 
+bool IsNewPermissionMessageSystemEnabled() {
+  const std::string group_name =
+      base::FieldTrialList::FindFullName("PermissionMessageSystem");

[Yoyo Zhou, 2015/03/12 20:55:57]

You haven't defined this field trial yet (see field_trial.h documentation). IMO
you should do so in this patch, because otherwise we're asking about a
nonexistent field trial. The trial can start out with 100% of users not using
the new system.

[Marc Treib, 2015/03/13 10:43:09]

My intention was to enable this through Finch. In that case, I think we mustn't
define the field trial in Chrome (see go/finch-guide).

[Yoyo Zhou, 2015/03/13 18:08:13]

Ok.

+  return group_name == "NewSystem";
+}
+
 typedef std::set<PermissionMessage> PermissionMsgSet;
 
 template<typename T>
@@ -155,6 +162,40 @@ PermissionMessages ChromePermissionMessageProvider::GetPermissionMessages(
   return messages;
 }
 
+PermissionMessageStrings
+ChromePermissionMessageProvider::GetPermissionMessageStrings(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  PermissionMessageStrings strings;
+  if (IsNewPermissionMessageSystemEnabled()) {
+    CoalescedPermissionMessages messages = GetCoalescedPermissionMessages(
+        GetAllPermissionIDs(permissions, extension_type));
+    for (const CoalescedPermissionMessage& msg : messages)
+      strings.push_back(PermissionMessageString(msg));
+  } else {
+    std::vector<base::string16> messages =
+        GetLegacyWarningMessages(permissions, extension_type);
+    std::vector<base::string16> details =
+        GetLegacyWarningMessagesDetails(permissions, extension_type);
+    DCHECK_EQ(messages.size(), details.size());
+    for (size_t i = 0; i < messages.size(); i++)
+      strings.push_back(PermissionMessageString(messages[i], details[i]));
+  }
+  return strings;
+}
+
+PermissionMessageIDs
+ChromePermissionMessageProvider::GetLegacyPermissionMessageIDs(
+    const PermissionSet* permissions,
+    Manifest::Type extension_type) const {
+  PermissionMessageIDs ids;
+  for (const PermissionMessage& msg :
+       GetPermissionMessages(permissions, extension_type)) {
+    ids.push_back(msg.id());
+  }
+  return ids;
+}
+
 CoalescedPermissionMessages
 ChromePermissionMessageProvider::GetCoalescedPermissionMessages(
     const PermissionIDSet& permissions) const {
@@ -185,7 +226,8 @@ ChromePermissionMessageProvider::GetCoalescedPermissionMessages(
   return messages;
 }
 
-std::vector<base::string16> ChromePermissionMessageProvider::GetWarningMessages(
+std::vector<base::string16>
+ChromePermissionMessageProvider::GetLegacyWarningMessages(
     const PermissionSet* permissions,
     Manifest::Type extension_type) const {
   std::vector<base::string16> message_strings;
@@ -198,7 +240,7 @@ std::vector<base::string16> ChromePermissionMessageProvider::GetWarningMessages(
 }
 
 std::vector<base::string16>
-ChromePermissionMessageProvider::GetWarningMessagesDetails(
+ChromePermissionMessageProvider::GetLegacyWarningMessagesDetails(
     const PermissionSet* permissions,
     Manifest::Type extension_type) const {
   std::vector<base::string16> message_strings;