Refactor resolution code in the vm to properly handle ambiguity errors.

runtime/vm/intrinsifier_arm.cc

Index: runtime/vm/intrinsifier_arm.cc
===================================================================
--- runtime/vm/intrinsifier_arm.cc	(revision 25291)
+++ runtime/vm/intrinsifier_arm.cc	(working copy)
@@ -170,8 +170,8 @@
 
 static intptr_t ComputeObjectArrayTypeArgumentsOffset() {
   const Library& core_lib = Library::Handle(Library::CoreLibrary());
-  const Class& cls =
-      Class::Handle(core_lib.LookupClassAllowPrivate(Symbols::ObjectArray()));
+  const Class& cls = Class::Handle(
+      core_lib.LookupClassAllowPrivate(Symbols::ObjectArray(), NULL));
   ASSERT(!cls.IsNull());
   ASSERT(cls.HasTypeArguments());
   ASSERT(cls.NumTypeArguments() == 1);
@@ -1368,8 +1368,8 @@
 bool Intrinsifier::Random_nextState(Assembler* assembler) {
   const Library& math_lib = Library::Handle(Library::MathLibrary());
   ASSERT(!math_lib.IsNull());
-  const Class& random_class =
-      Class::Handle(math_lib.LookupClassAllowPrivate(Symbols::_Random()));
+  const Class& random_class = Class::Handle(
+      math_lib.LookupClassAllowPrivate(Symbols::_Random(), NULL));
   ASSERT(!random_class.IsNull());
   const Field& state_field = Field::ZoneHandle(
       random_class.LookupInstanceField(Symbols::_state()));