Make ART compile with GCC -O0 again.

Tidy up InstructionSetFeatures so that it has a type hierarchy dependent on
architecture.
Add to instruction_set_test to warn when InstructionSetFeatures don't agree
with ones from system properties, AT_HWCAP and /proc/cpuinfo.
Clean-up class linker entry point logic to not return entry points but to
test whether the passed code is the particular entrypoint. This works around
image trampolines that replicate entrypoints.
Bug: 17993736

Change-Id: I5f4b49e88c3b02a79f9bee04f83395146ed7be23
diff --git a/runtime/reflection.cc b/runtime/reflection.cc
index 23f8076..b57e48f 100644
--- a/runtime/reflection.cc
+++ b/runtime/reflection.cc
@@ -19,6 +19,7 @@
 #include "class_linker.h"
 #include "common_throws.h"
 #include "dex_file-inl.h"
+#include "entrypoints/entrypoint_utils.h"
 #include "jni_internal.h"
 #include "method_helper-inl.h"
 #include "mirror/art_field-inl.h"
@@ -528,7 +529,7 @@
 }
 
 void InvokeWithShadowFrame(Thread* self, ShadowFrame* shadow_frame, uint16_t arg_offset,
-                           MethodHelper& mh, JValue* result) {
+                           MethodHelper* mh, JValue* result) {
   // We want to make sure that the stack is not within a small distance from the
   // protected region in case we are calling into a leaf function whose stack
   // check has been elided.
@@ -537,10 +538,10 @@
     return;
   }
 
-  ArgArray arg_array(mh.GetShorty(), mh.GetShortyLength());
+  ArgArray arg_array(mh->GetShorty(), mh->GetShortyLength());
   arg_array.BuildArgArrayFromFrame(shadow_frame, arg_offset);
   shadow_frame->GetMethod()->Invoke(self, arg_array.GetArray(), arg_array.GetNumBytes(), result,
-                                    mh.GetShorty());
+                                    mh->GetShorty());
 }
 
 jobject InvokeMethod(const ScopedObjectAccessAlreadyRunnable& soa, jobject javaMethod,