Simplify and improve optimization of is-tests in the precompiler.

runtime/vm/raw_object.h

Index: runtime/vm/raw_object.h
diff --git a/runtime/vm/raw_object.h b/runtime/vm/raw_object.h
index 8f6f624160be228c177535c1b1b0afae06aad9e0..286a5f9899146e429cdb6afbba1364e45a600f26 100644
--- a/runtime/vm/raw_object.h
+++ b/runtime/vm/raw_object.h
@@ -2281,10 +2281,7 @@ inline bool RawObject::IsTwoByteStringClassId(intptr_t index) {
                  kTwoByteStringCid == kStringCid + 2 &&
                  kExternalOneByteStringCid == kStringCid + 3 &&
                  kExternalTwoByteStringCid == kStringCid + 4);
-  return (index == kOneByteStringCid ||

[Vyacheslav Egorov (Google), 2016/06/16 08:37:37]

I wonder how this worked

-          index == kTwoByteStringCid ||
-          index == kExternalOneByteStringCid ||
-          index == kExternalTwoByteStringCid);
+  return (index == kTwoByteStringCid || index == kExternalTwoByteStringCid);
 }