Fully implement string interning.

Also, more const.

Change-Id: I09cae88d677e8e6e42d0fa9b5d1093c79d225e66
diff --git a/src/runtime.h b/src/runtime.h
index 2717843..922eeab 100644
--- a/src/runtime.h
+++ b/src/runtime.h
@@ -23,6 +23,7 @@
 class ClassLinker;
 class DexFile;
 class Heap;
+class InternTable;
 class JavaVMExt;
 class SignalCatcher;
 class String;
@@ -92,6 +93,10 @@
     return class_linker_;
   }
 
+  InternTable* GetInternTable() const {
+    return intern_table_;
+  }
+
   JavaVMExt* GetJavaVM() const {
     return java_vm_;
   }
@@ -101,7 +106,7 @@
  private:
   static void PlatformAbort(const char*, int);
 
-  Runtime() : stack_size_(0), thread_list_(NULL), class_linker_(NULL) {}
+  Runtime() : stack_size_(0), thread_list_(NULL), intern_table_(NULL), class_linker_(NULL) {}
 
   void BlockSignals();
 
@@ -114,6 +119,8 @@
 
   ThreadList* thread_list_;
 
+  InternTable* intern_table_;
+
   ClassLinker* class_linker_;
 
   SignalCatcher* signal_catcher_;