ART: Clean up compiler

Clean up the compiler: less extern functions, dis-entangle
compilers, hide some compiler specifics, lower global includes.

Change-Id: Ibaf88d02505d86994d7845cf0075be5041cc8438
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index 3915381..3b0c8af 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -444,7 +444,7 @@
   // Lazily create thread-local storage
   CompilerTls* res = static_cast<CompilerTls*>(pthread_getspecific(tls_key_));
   if (res == NULL) {
-    res = new CompilerTls();
+    res = compiler_->CreateNewCompilerTls();
     CHECK_PTHREAD_CALL(pthread_setspecific, (tls_key_, res), "compiler tls");
   }
   return res;