Replace OStream with std::ostream.

src/basic-block-profiler.h

Index: src/basic-block-profiler.h
diff --git a/src/basic-block-profiler.h b/src/basic-block-profiler.h
index 58e85427ea06ff426b3bbf14fcdaca7a7cd4596e..99fa3b172dbf750eee51c9cb5b4daf825ce5181e 100644
--- a/src/basic-block-profiler.h
+++ b/src/basic-block-profiler.h
@@ -5,7 +5,9 @@
 #ifndef V8_BASIC_BLOCK_PROFILER_H_
 #define V8_BASIC_BLOCK_PROFILER_H_
 
+#include <iosfwd>
 #include <list>
+#include <string>
 
 #include "src/v8.h"
 
@@ -22,15 +24,16 @@ class BasicBlockProfiler {
     size_t n_blocks() const { return n_blocks_; }
     const uint32_t* counts() const { return &counts_[0]; }
 
-    void SetCode(OStringStream* os);
-    void SetFunctionName(OStringStream* os);
-    void SetSchedule(OStringStream* os);
+    void SetCode(std::ostringstream* os);
+    void SetFunctionName(std::ostringstream* os);
+    void SetSchedule(std::ostringstream* os);
     void SetBlockId(size_t offset, size_t block_id);
     uint32_t* GetCounterAddress(size_t offset);
 
    private:
     friend class BasicBlockProfiler;
-    friend OStream& operator<<(OStream& os, const BasicBlockProfiler::Data& s);
+    friend std::ostream& operator<<(std::ostream& os,
+                                    const BasicBlockProfiler::Data& s);
 
     explicit Data(size_t n_blocks);
     ~Data();
@@ -57,15 +60,16 @@ class BasicBlockProfiler {
   const DataList* data_list() { return &data_list_; }
 
  private:
-  friend OStream& operator<<(OStream& os, const BasicBlockProfiler& s);
+  friend std::ostream& operator<<(std::ostream& os,
+                                  const BasicBlockProfiler& s);
 
   DataList data_list_;
 
   DISALLOW_COPY_AND_ASSIGN(BasicBlockProfiler);
 };
 
-OStream& operator<<(OStream& os, const BasicBlockProfiler& s);
-OStream& operator<<(OStream& os, const BasicBlockProfiler::Data& s);
+std::ostream& operator<<(std::ostream& os, const BasicBlockProfiler& s);
+std::ostream& operator<<(std::ostream& os, const BasicBlockProfiler::Data& s);
 
 }  // namespace internal
 }  // namespace v8