Move hashmap into base/.

src/arm64/simulator-arm64.h

Index: src/arm64/simulator-arm64.h
diff --git a/src/arm64/simulator-arm64.h b/src/arm64/simulator-arm64.h
index 586f204be503eb8a782693335b4a3d5465a08b8a..cc2dcc2024a6d9a3e7103fd9658cd3f8c9638494 100644
--- a/src/arm64/simulator-arm64.h
+++ b/src/arm64/simulator-arm64.h
@@ -151,8 +151,7 @@ typedef SimRegisterBase SimFPRegister;    // v0-v31
 
 class Simulator : public DecoderVisitor {
  public:
-  static void FlushICache(v8::internal::HashMap* i_cache, void* start,
-                          size_t size) {
+  static void FlushICache(base::HashMap* i_cache, void* start, size_t size) {
     USE(i_cache);
     USE(start);
     USE(size);
@@ -168,7 +167,7 @@ class Simulator : public DecoderVisitor {
 
   static void Initialize(Isolate* isolate);
 
-  static void TearDown(HashMap* i_cache, Redirection* first);
+  static void TearDown(base::HashMap* i_cache, Redirection* first);
 
   static Simulator* current(v8::internal::Isolate* isolate);