Add inline non-transcendental cache version of log to lithium.

src/hydrogen.cc

Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc	(revision 7492)
+++ src/hydrogen.cc	(working copy)
@@ -3919,11 +3919,16 @@
     return false;
   }
 
-  // Don't inline deeper than two calls.
+  // Don't inline deeper than kMaxInliningLevels calls.
   HEnvironment* env = environment();
-  if (env->outer() != NULL && env->outer()->outer() != NULL) {
-    TraceInline(target, "inline depth limit reached");
-    return false;
+  int current_level = 1;
+  while (env->outer() != NULL) {
+    if (current_level == Compiler::kMaxInliningLevels) {
+      TraceInline(target, "inline depth limit reached");
+      return false;
+    }
+    current_level++;
+    env = env->outer();
   }
 
   // Don't inline recursive functions.