Revert of Reland "Remove support for thread-based recompilation"

src/runtime/runtime-compiler.cc

Index: src/runtime/runtime-compiler.cc
diff --git a/src/runtime/runtime-compiler.cc b/src/runtime/runtime-compiler.cc
index 16175803f05a76d91b2ccdb9515b2ba0c39d26f3..d8512fdfb540b546badd2fe7e72303fd629ce27f 100644
--- a/src/runtime/runtime-compiler.cc
+++ b/src/runtime/runtime-compiler.cc
@@ -232,9 +232,8 @@
     // Gate the OSR entry with a stack check.
     BackEdgeTable::AddStackCheck(caller_code, pc_offset);
     // Poll already queued compilation jobs.
-    OptimizingCompileDispatcher* dispatcher =
-        isolate->optimizing_compile_dispatcher();
-    if (dispatcher->IsQueuedForOSR(function, ast_id)) {
+    OptimizingCompilerThread* thread = isolate->optimizing_compiler_thread();
+    if (thread->IsQueuedForOSR(function, ast_id)) {
       if (FLAG_trace_osr) {
         PrintF("[OSR - Still waiting for queued: ");
         function->PrintName();
@@ -243,7 +242,7 @@
       return NULL;
     }
 
-    job = dispatcher->FindReadyOSRCandidate(function, ast_id);
+    job = thread->FindReadyOSRCandidate(function, ast_id);
   }
 
   if (job != NULL) {
@@ -325,7 +324,7 @@
     return isolate->StackOverflow();
   }
 
-  isolate->optimizing_compile_dispatcher()->InstallOptimizedFunctions();
+  isolate->optimizing_compiler_thread()->InstallOptimizedFunctions();
   return (function->IsOptimized()) ? function->code()
                                    : function->shared()->code();
 }