[Compiler] Put background compilation of eager inner functions behind a flag.

Disabled until clusterfuzz issues are sorted.

BUG=v8:5203, v8:5215, chromium:685515, chromium:685476

Review-Url: https://codereview.chromium.org/2658803002
Cr-Commit-Position: refs/heads/master@{#42686}

src/compiler.cc

@@ -386,7 +386,8 @@ bool UseCompilerDispatcher(CompilerDispatcher* dispatcher,
                            DeclarationScope* scope,
                            Handle<SharedFunctionInfo> shared_info,
                            bool is_debug, bool will_serialize) {
-  return dispatcher->IsEnabled() && !is_debug && !will_serialize &&
+  return FLAG_compiler_dispatcher_eager_inner && dispatcher->IsEnabled() &&
+         !is_debug && !will_serialize &&
          !UseAsmWasm(scope, shared_info, is_debug);
 }
 

src/flag-definitions.h

@@ -679,6 +679,8 @@ DEFINE_BOOL(cache_prototype_transitions, true, "cache prototype transitions")
 
 // compiler-dispatcher.cc
 DEFINE_BOOL(compiler_dispatcher, false, "enable compiler dispatcher")
+DEFINE_BOOL(compiler_dispatcher_eager_inner, false,
+            "enable background compilation of eager inner functions")
 DEFINE_BOOL(trace_compiler_dispatcher, false,
             "trace compiler dispatcher activity")