Tree-shaker: Use insertion in the work queue instead of "was compiled" as the criterion to retain a…

runtime/vm/precompiler.cc

Index: runtime/vm/precompiler.cc
diff --git a/runtime/vm/precompiler.cc b/runtime/vm/precompiler.cc
index 6502f6570746f4c95267ceb68e50973fe83518dc..c9894285d7aa978a173fa767b965439d00babd2a 100644
--- a/runtime/vm/precompiler.cc
+++ b/runtime/vm/precompiler.cc
@@ -618,6 +618,7 @@ void Precompiler::ProcessFunction(const Function& function) {
 
   ASSERT(function.HasCode());
   AddCalleesOf(function);
+  AddTypesOf(function);
 }
 
 
@@ -1383,7 +1384,7 @@ void Precompiler::TraceForRetainedFunctions() {
       functions = cls.functions();
       for (intptr_t j = 0; j < functions.Length(); j++) {
         function ^= functions.At(j);
-        bool retain = function.HasCode();
+        bool retain = functions_to_retain_.Lookup(&function) != NULL;
         if (!retain && function.HasImplicitClosureFunction()) {
           // It can happen that all uses of an implicit closure inline their
           // target function, leaving the target function uncompiled. Keep
@@ -1394,7 +1395,6 @@ void Precompiler::TraceForRetainedFunctions() {
         }
         if (retain) {
           function.DropUncompiledImplicitClosureFunction();
-          AddTypesOf(function);
         }
       }
     }
@@ -1403,10 +1403,8 @@ void Precompiler::TraceForRetainedFunctions() {
   closures = isolate()->object_store()->closure_functions();
   for (intptr_t j = 0; j < closures.Length(); j++) {
     function ^= closures.At(j);
-    bool retain = function.HasCode();
+    bool retain = functions_to_retain_.Lookup(&function) != NULL;
     if (retain) {
-      AddTypesOf(function);
-
       cls = function.Owner();
       AddTypesOf(cls);