Begin implementing flag --deoptimize-filter=FUNC for ia32.

runtime/vm/flow_graph_compiler.cc

Index: runtime/vm/flow_graph_compiler.cc
diff --git a/runtime/vm/flow_graph_compiler.cc b/runtime/vm/flow_graph_compiler.cc
index 6cfea3213dfc31132f3c50e87f5784277149e6cb..5ba1ab79c7963a5158cdf53abdb5b5d82311a500 100644
--- a/runtime/vm/flow_graph_compiler.cc
+++ b/runtime/vm/flow_graph_compiler.cc
@@ -35,6 +35,8 @@ DECLARE_FLAG(bool, use_cha);
 DECLARE_FLAG(bool, use_osr);
 DEFINE_FLAG(bool, enable_simd_inline, true,
     "Enable inlining of SIMD related method calls.");
+DEFINE_FLAG(charp, deoptimize_filter, NULL,
+            "Force deoptimization in named function");
 
 // Assign locations to incoming arguments, i.e., values pushed above spill slots
 // with PushArgument.  Recursively allocates from outermost to innermost
@@ -169,6 +171,14 @@ bool FlowGraphCompiler::CanOSRFunction() const {
 }
 
 
+bool FlowGraphCompiler::ShouldDeoptimizeFunction() const {
+  return (is_optimizing() &&
+          (FLAG_deoptimize_filter != NULL) &&
+          (strstr(parsed_function().function().ToFullyQualifiedCString(),
+                  FLAG_deoptimize_filter) != NULL));
+}
+
+
 static bool IsEmptyBlock(BlockEntryInstr* block) {
   return !block->HasParallelMove() &&
          block->next()->IsGoto() &&