Remove memory corruption testing from base::File().

base/files/file.h

Index: base/files/file.h
diff --git a/base/files/file.h b/base/files/file.h
index cba435363560187f60341cad8c865ed1d576b291..976188b232efdac7ad6c3594bd4d6e5c273cffe9 100644
--- a/base/files/file.h
+++ b/base/files/file.h
@@ -21,7 +21,6 @@
 #include "base/files/file_path.h"
 #include "base/files/file_tracing.h"
 #include "base/files/scoped_file.h"
-#include "base/gtest_prod_util.h"
 #include "base/move.h"
 #include "base/time/time.h"
 
@@ -29,8 +28,6 @@
 #include "base/win/scoped_handle.h"
 #endif
 
-FORWARD_DECLARE_TEST(FileTest, MemoryCorruption);
-
 namespace base {
 
 #if defined(OS_WIN)
@@ -306,55 +303,8 @@ class BASE_EXPORT File {
   static std::string ErrorToString(Error error);
 
  private:
-  FRIEND_TEST_ALL_PREFIXES(::FileTest, MemoryCorruption);
-
   friend class FileTracing::ScopedTrace;
 
-#if defined(OS_POSIX)
-  // Encloses a single ScopedFD, saving a cheap tamper resistent memory checksum
-  // alongside it. This checksum is validated at every access, allowing early
-  // detection of memory corruption.
-
-  // TODO(gavinp): This is in place temporarily to help us debug
-  // https://crbug.com/424562 , which can't be reproduced in valgrind. Remove
-  // this code after we have fixed this issue.
-  class MemoryCheckingScopedFD {
-   public:
-    MemoryCheckingScopedFD();
-    MemoryCheckingScopedFD(int fd);
-    ~MemoryCheckingScopedFD();
-
-    bool is_valid() const { Check(); return file_.is_valid(); }
-    int get() const { Check(); return file_.get(); }
-
-    void reset() { Check(); file_.reset(); UpdateChecksum(); }
-    void reset(int fd) { Check(); file_.reset(fd); UpdateChecksum(); }
-    int release() {
-      Check();
-      int fd = file_.release();
-      UpdateChecksum();
-      return fd;
-    }
-
-   private:
-    FRIEND_TEST_ALL_PREFIXES(::FileTest, MemoryCorruption);
-
-    // Computes the checksum for the current value of |file_|. Returns via an
-    // out parameter to guard against implicit conversions of unsigned integral
-    // types.
-    void ComputeMemoryChecksum(unsigned int* out_checksum) const;
-
-    // Confirms that the current |file_| and |file_memory_checksum_| agree,
-    // failing a CHECK if they do not.
-    void Check() const;
-
-    void UpdateChecksum();
-
-    ScopedFD file_;
-    unsigned int file_memory_checksum_;
-  };
-#endif
-
   // Creates or opens the given file. Only called if |path| has no
   // traversal ('..') components.
   void DoInitialize(const FilePath& path, uint32 flags);
@@ -368,7 +318,7 @@ class BASE_EXPORT File {
 #if defined(OS_WIN)
   win::ScopedHandle file_;
 #elif defined(OS_POSIX)
-  MemoryCheckingScopedFD file_;
+  ScopedFD file_;
 #endif
 
   // A path to use for tracing purposes. Set if file tracing is enabled during
@@ -386,3 +336,4 @@ class BASE_EXPORT File {
 }  // namespace base
 
 #endif  // BASE_FILES_FILE_H_
+