ART: Run GraphChecker after Builder and SsaBuilder

This patch refactors the way GraphChecker is invoked, utilizing the
same scoping mechanism as pass timing and graph visualizer. Therefore,
GraphChecker will now run not just after instances of HOptimization
but after the builders and reg alloc, too.

Change-Id: I8173b98b79afa95e1fcbf3ac9630a873d7f6c1d4
diff --git a/compiler/optimizing/dead_code_elimination.h b/compiler/optimizing/dead_code_elimination.h
index 59a57c4..8d6008b 100644
--- a/compiler/optimizing/dead_code_elimination.h
+++ b/compiler/optimizing/dead_code_elimination.h
@@ -32,7 +32,7 @@
   HDeadCodeElimination(HGraph* graph,
                        OptimizingCompilerStats* stats = nullptr,
                        const char* name = kInitialDeadCodeEliminationPassName)
-      : HOptimization(graph, true, name, stats) {}
+      : HOptimization(graph, name, stats) {}
 
   void Run() OVERRIDE;