Remove MethodHelper from the interpreter.

Use ShadowFrame to get the executing method to avoid a handle for the current
method.
Various associated bits of header file clean-up and removal of an unnecessary
use of MethodHelper in CompilerDriver.

Change-Id: I3b6f4413701e8fc6b0c58b0041a0dd15472bedaa
diff --git a/runtime/mirror/art_method.h b/runtime/mirror/art_method.h
index da494e0..0466fe3 100644
--- a/runtime/mirror/art_method.h
+++ b/runtime/mirror/art_method.h
@@ -32,15 +32,14 @@
 struct ArtMethodOffsets;
 struct ConstructorMethodOffsets;
 union JValue;
-class MethodHelper;
 class ScopedObjectAccessAlreadyRunnable;
 class StringPiece;
 class ShadowFrame;
 
 namespace mirror {
 
-typedef void (EntryPointFromInterpreter)(Thread* self, MethodHelper* mh,
-    const DexFile::CodeItem* code_item, ShadowFrame* shadow_frame, JValue* result);
+typedef void (EntryPointFromInterpreter)(Thread* self, const DexFile::CodeItem* code_item,
+                                         ShadowFrame* shadow_frame, JValue* result);
 
 #define ART_METHOD_HAS_PADDING_FIELD_ON_64_BIT