Canonicalize types.

runtime/vm/raw_object.h

Index: runtime/vm/raw_object.h
===================================================================
--- runtime/vm/raw_object.h	(revision 1042)
+++ runtime/vm/raw_object.h	(working copy)
@@ -204,6 +204,7 @@
   RawType* signature_type_;  // Cached function type for signature class.
   RawArray* functions_cache_;  // See class FunctionsCache.
   RawArray* constants_;  // Canonicalized values of this class.
+  RawArray* canonical_types_;  // Canonicalized types of this class.
   RawCode* allocation_stub_;  // Stub code for allocation of instances.
   RawObject** to() {
     return reinterpret_cast<RawObject**>(&ptr()->allocation_stub_);
@@ -214,6 +215,7 @@
   ObjectKind instance_kind_;
   intptr_t type_arguments_instance_field_offset_;  // May be kNoTypeArguments.
   intptr_t num_constants_;  // Number of objects in constants_ array.
+  intptr_t num_canonical_types_;  // Number of types in canonical_types_ array.
   intptr_t next_field_offset_;  // Offset of then next instance field.
   intptr_t num_native_fields_;  // Number of native fields in class.
   int8_t class_state_;  // Of type ClassState.