[turbofan] Don't take into account source size for inlining heuristics.

The source size is not a real indicator for whether or not to inline a
certain function.

R=ishell@chromium.org, jarin@chromium.org
BUG=v8:3354,v8:5267

Review URL: https://codereview.chromium.org/2361813002 .

Cr-Commit-Position: refs/heads/master@{#39659}

src/compiler/js-inlining-heuristic.cc

@@ -49,11 +49,6 @@ bool CanInlineFunction(Handle<JSFunction> function) {
   // Don't inline builtins.
   if (function->shared()->IsBuiltin()) return false;
 
-  // Quick check on source code length to avoid parsing large candidate.
-  if (function->shared()->SourceSize() > FLAG_max_inlined_source_size) {
-    return false;
-  }
-
   // Quick check on the size of the AST to avoid parsing large candidate.
   if (function->shared()->ast_node_count() > FLAG_max_inlined_nodes) {
     return false;
@@ -287,9 +282,7 @@ void JSInliningHeuristic::PrintCandidates() {
            candidate.node->op()->mnemonic(), candidate.frequency);
     for (int i = 0; i < candidate.num_functions; ++i) {
       Handle<JSFunction> function = candidate.functions[i];
-      PrintF("  - size[source]:%d, size[ast]:%d, name: %s\n",
-             function->shared()->SourceSize(),
-             function->shared()->ast_node_count(),
+      PrintF("  - size:%d, name: %s\n", function->shared()->ast_node_count(),
              function->shared()->DebugName()->ToCString().get());
     }
   }

test/cctest/test-heap-profiler.cc

@@ -2583,6 +2583,7 @@ TEST(TrackHeapAllocationsWithInlining) {
 }
 
 TEST(TrackHeapAllocationsWithoutInlining) {
+  i::FLAG_turbo_inlining = false;
   i::FLAG_max_inlined_source_size = 0;  // Disable inlining
   v8::HandleScope scope(v8::Isolate::GetCurrent());
   LocalContext env;

test/mjsunit/es6/tail-call-megatest.js

@@ -25,10 +25,11 @@ function checkStackTrace(expected) {
 
 var CAN_INLINE_COMMENT  = "// Let it be inlined.";
 var DONT_INLINE_COMMENT = (function() {
-  var line = "// Don't inline. Don't inline. Don't inline. Don't inline.";
-  for (var i = 0; i < 4; i++) {
-    line += "\n  " + line;
+  var line = "1";
+  for (var i = 0; i < 200; ++i) {
+    line += "," + i;
   }
+  line += ";\n";
   return line;
 })();