Remove use of deprecated base::ListValue::Append(Value*) overload in extensions.

extensions/common/permissions/manifest_permission.cc

Index: extensions/common/permissions/manifest_permission.cc
diff --git a/extensions/common/permissions/manifest_permission.cc b/extensions/common/permissions/manifest_permission.cc
index 9315d1d0418d8d0ff78d11565f40a9d33b5c894d..beb8fe3e5f03715754ce8d226c02977faa4f5188 100644
--- a/extensions/common/permissions/manifest_permission.cc
+++ b/extensions/common/permissions/manifest_permission.cc
@@ -29,15 +29,13 @@ bool ManifestPermission::Equal(const ManifestPermission* rhs) const {
 
 void ManifestPermission::GetSize(base::PickleSizer* s) const {
   base::ListValue singleton;
-  base::Value* value = ToValue().release();
-  singleton.Append(value);
+  singleton.Append(ToValue());
   IPC::GetParamSize(s, singleton);
 }
 
 void ManifestPermission::Write(base::Pickle* m) const {
   base::ListValue singleton;
-  base::Value* value = ToValue().release();
-  singleton.Append(value);
+  singleton.Append(ToValue());
   IPC::WriteParam(m, singleton);
 }