Rename compiler_llvm CompilationUnit to LlvmCompilationUnit

Also fixed stray ART_TEST_CFLAGS to LOCAL_CFLAGS
Also fixed relative includes

Tried to change CompilationUnit to reference LlvmCompilationUnit, but
that causes issues because of the split libart-compiler
libart-compiler-llvm.

Change-Id: I7a490f339add6355a20c1cedae858ccf6967a6aa
diff --git a/src/compiler/codegen/codegen_util.h b/src/compiler/codegen/codegen_util.h
index 3bb4291..4f14656 100644
--- a/src/compiler/codegen/codegen_util.h
+++ b/src/compiler/codegen/codegen_util.h
@@ -17,8 +17,15 @@
 #ifndef ART_SRC_COMPILER_CODEGEN_CODEGENUTIL_H_
 #define ART_SRC_COMPILER_CODEGEN_CODEGENUTIL_H_
 
+#include <stdint.h>
+
+#include "compiler/compiler_enums.h"
+
 namespace art {
 
+class CompilationUnit;
+struct LIR;
+
 void MarkSafepointPC(CompilationUnit* cu, LIR* inst);
 bool FastInstance(CompilationUnit* cu,  uint32_t field_idx,
                   int& field_offset, bool& is_volatile, bool is_put);