Move stack map stream implementation to its own cc file.

It's big enough now to separate the implementation from the header.

It also enables faster compilation time for experiments.

Change-Id: Ica0c72994d5e461c62c32628010f46f9e5c46b57
diff --git a/compiler/Android.mk b/compiler/Android.mk
index ac95abd..3458784 100644
--- a/compiler/Android.mk
+++ b/compiler/Android.mk
@@ -124,13 +124,14 @@
 	optimizing/optimizing_compiler.cc \
 	optimizing/parallel_move_resolver.cc \
 	optimizing/prepare_for_register_allocation.cc \
+	optimizing/primitive_type_propagation.cc \
+	optimizing/reference_type_propagation.cc \
 	optimizing/register_allocator.cc \
 	optimizing/side_effects_analysis.cc \
 	optimizing/ssa_builder.cc \
 	optimizing/ssa_liveness_analysis.cc \
 	optimizing/ssa_phi_elimination.cc \
-	optimizing/primitive_type_propagation.cc \
-	optimizing/reference_type_propagation.cc \
+	optimizing/stack_map_stream.cc \
 	trampolines/trampoline_compiler.cc \
 	utils/arena_bit_vector.cc \
 	utils/arm/assembler_arm.cc \