mac: Delete some pre-10.5 code.

base/debug/stack_trace_posix.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/debug/stack_trace.h"
 
 #include <errno.h>
 #include <execinfo.h>
 #include <fcntl.h>
 #include <stdio.h>
@@ skipping 130 matching lines @@
     }
   }
 #endif  // defined(USE_SYMBOLIZE)
 
   return symbolized;
 }
 
 }  // namespace
 
 StackTrace::StackTrace() {
-#if defined(OS_MACOSX) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5
-  if (backtrace == NULL) {
-    count_ = 0;
-    return;
-  }
-#endif
   // Though the backtrace API man page does not list any possible negative
   // return values, we take no chance.
   count_ = std::max(backtrace(trace_, arraysize(trace_)), 0);
 }
 
 void StackTrace::PrintBacktrace() const {
-#if defined(OS_MACOSX) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5
-  if (backtrace_symbols_fd == NULL)
-    return;
-#endif
   fflush(stderr);
   std::vector<std::string> trace_strings;
   GetBacktraceStrings(trace_, count_, &trace_strings, NULL);
   for (size_t i = 0; i < trace_strings.size(); ++i) {
     fprintf(stderr, "\t%s\n", trace_strings[i].c_str());
   }
 }
 
 void StackTrace::OutputToStream(std::ostream* os) const {
-#if defined(OS_MACOSX) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5
-  if (backtrace_symbols == NULL)
-    return;
-#endif
   std::vector<std::string> trace_strings;
   std::string error_message;
   if (GetBacktraceStrings(trace_, count_, &trace_strings, &error_message)) {
     (*os) << "Backtrace:\n";
   } else {
     if (!error_message.empty())
       error_message = " (" + error_message + ")";
     (*os) << "Unable to get symbols for backtrace" << error_message << ". "
           << "Dumping raw addresses in trace:\n";
   }
 
   for (size_t i = 0; i < trace_strings.size(); ++i) {
     (*os) << "\t" << trace_strings[i] << "\n";
   }
 }
 
 }  // namespace debug
 }  // namespace base