Add OptimizingCompilerStats to the CodeGenerator class.

Just refactoring, not yet used, but will be used by the incoming patch
series and future CodeGen specific stats.

Change-Id: I7d20489907b82678120518a77bdab9c4cc58f937
Signed-off-by: Serban Constantinescu <serban.constantinescu@linaro.org>
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 72c690d..3421fae 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -429,7 +429,8 @@
 
 CodeGeneratorX86::CodeGeneratorX86(HGraph* graph,
                    const X86InstructionSetFeatures& isa_features,
-                   const CompilerOptions& compiler_options)
+                   const CompilerOptions& compiler_options,
+                   OptimizingCompilerStats* stats)
     : CodeGenerator(graph,
                     kNumberOfCpuRegisters,
                     kNumberOfXmmRegisters,
@@ -437,8 +438,9 @@
                     ComputeRegisterMask(reinterpret_cast<const int*>(kCoreCalleeSaves),
                                         arraysize(kCoreCalleeSaves))
                         | (1 << kFakeReturnRegister),
-                        0,
-                        compiler_options),
+                    0,
+                    compiler_options,
+                    stats),
       block_labels_(graph->GetArena(), 0),
       location_builder_(graph, this),
       instruction_visitor_(graph, this),