Add a compilation tracing mechanism to the new compiler.

Code mostly imported from: https://android-review.googlesource.com/#/c/81653/.

Change-Id: I150fe942be0fb270e03fabb19032180f7a065d13
diff --git a/compiler/Android.mk b/compiler/Android.mk
index 1b70d59..8592aaa 100644
--- a/compiler/Android.mk
+++ b/compiler/Android.mk
@@ -82,6 +82,7 @@
 	optimizing/code_generator.cc \
 	optimizing/code_generator_arm.cc \
 	optimizing/code_generator_x86.cc \
+	optimizing/graph_visualizer.cc \
 	optimizing/nodes.cc \
 	optimizing/optimizing_compiler.cc \
 	optimizing/ssa_builder.cc \