Report PPAPI plugin load error code to UMA.

base/native_library_mac.mm

 // Copyright (c) 2011 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/native_library.h"
 
+#include <ostream>
+
 #include <dlfcn.h>
 #include <mach-o/getsect.h>
 
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
@@ skipping 18 matching lines @@
       SEG_DATA, "__objc_imageinfo");
 #else
   const section* section = getsectbynamefromheader(
       reinterpret_cast<const struct mach_header*>(info.dli_fbase),
       SEG_OBJC, "__image_info");
 #endif
   return section == NULL ? OBJC_NOT_PRESENT : OBJC_PRESENT;
 }
 
 // static
+// TODO(xhwang): Fill |error|. See http://crbug.com/353771
 NativeLibrary LoadNativeLibrary(const base::FilePath& library_path,
-                                std::string* error) {
+                                NativeLibraryLoadError* /* error */) {
   // dlopen() etc. open the file off disk.
   if (library_path.Extension() == "dylib" || !DirectoryExists(library_path)) {
     void* dylib = dlopen(library_path.value().c_str(), RTLD_LAZY);
     if (!dylib)
       return NULL;
     NativeLibrary native_lib = new NativeLibraryStruct();
     native_lib->type = DYNAMIC_LIB;
     native_lib->dylib = dylib;
     native_lib->objc_status = OBJC_UNKNOWN;
     return native_lib;
@@ skipping 58 matching lines @@
     library->objc_status = GetObjCStatusForImage(function_pointer);
 
   return function_pointer;
 }
 
 // static
 string16 GetNativeLibraryName(const string16& name) {
   return name + ASCIIToUTF16(".dylib");
 }
 
+// static
+std::ostream& operator<<(std::ostream& out,
+                         const NativeLibraryLoadError& error) {
+  return out << error.message;
+}
+
 }  // namespace base