[compiler] Ensure code unsupported by Crankshaft goes to Ignition.

src/runtime/runtime-test.cc

Index: src/runtime/runtime-test.cc
diff --git a/src/runtime/runtime-test.cc b/src/runtime/runtime-test.cc
index 199c423971195f571103b52cfb7813eebcdb36ae..b79ece4a0d6539812831c0b56e8e3cbf32fbac1a 100644
--- a/src/runtime/runtime-test.cc
+++ b/src/runtime/runtime-test.cc
@@ -127,6 +127,12 @@ RUNTIME_FUNCTION(Runtime_OptimizeFunctionOnNextCall) {
     return isolate->heap()->undefined_value();
   }
 
+  // If function isn't compiled, compile it now.
+  if (!function->is_compiled() &&

[Michael Starzinger, 2016/11/22 14:53:50]

Would it be possible to check whether {function->shared()->is_compiled()} here
instead? Note that {Compiler::Compile} already has the appropriate
post-condition check for {function->shared()->is_compiled()} in place. WDYT?

Also I would move this to after the quick-check for {function->IsOptimized()}
below (i.e. 3 lines down).

[rmcilroy, 2016/11/22 17:24:02]

Done.
This is what I had originally but it doesn't work because when --always-opt is
enabled the Compiler::Compile causes the code to get optimized, and
MarkForOptimization fails due to the code already being optimized.

+      !Compiler::Compile(function, Compiler::CLEAR_EXCEPTION)) {
+    return isolate->heap()->undefined_value();
+  }
+
   // If the function is already optimized, just return.
   if (function->IsOptimized()) return isolate->heap()->undefined_value();