Polymorphic inlining for some recognized methods in the optimizing compiler.

runtime/vm/intermediate_language.h

Index: runtime/vm/intermediate_language.h
===================================================================
--- runtime/vm/intermediate_language.h	(revision 26420)
+++ runtime/vm/intermediate_language.h	(working copy)
@@ -136,6 +136,11 @@
 
 // A list of core function that should always be inlined.
 #define INLINE_WHITE_LIST(V)                                                   \
+  V(_ObjectArray, get:length, ObjectArrayLength, 1441000484)                   \
+  V(_ImmutableArray, get:length, ImmutableArrayLength, 1430953867)             \
+  V(_TypedList, get:length, TypedDataLength, 117589485)                        \
+  V(_GrowableObjectArray, get:length, GrowableArrayLength, 767561362)          \
+  V(_StringBase, get:length, StringBaseLength, 1158042795)                     \
   V(ListIterator, moveNext, ListIteratorMoveNext, 657540761)                   \
   V(_GrowableObjectArray, get:iterator, GrowableArrayIterator, 281980741)      \
   V(_GrowableObjectArray, forEach, GrowableArrayForEach, 334448248)
@@ -2703,6 +2708,8 @@
     return instance_call()->PushArgumentAt(index);
   }
 
+  bool HasRecognizedTarget() const;
+
   DECLARE_INSTRUCTION(PolymorphicInstanceCall)
 
   const ICData& ic_data() const { return ic_data_; }