Revert of Move JoinString to the base namespace

content/browser/gpu/gpu_data_manager_impl_private.cc

 // Copyright (c) 2013 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 "content/browser/gpu/gpu_data_manager_impl_private.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
@@ skipping 548 matching lines @@
     if (update_histograms_)
       UpdateStats(gpu_info_, gpu_blacklist_.get(), features);
 
     UpdateBlacklistedFeatures(features);
   }
   if (gpu_driver_bug_list_) {
     gpu_driver_bugs_ = gpu_driver_bug_list_->MakeDecision(
         gpu::GpuControlList::kOsAny, std::string(), gpu_info_);
 
     disabled_extensions_ =
-        base::JoinString(gpu_driver_bug_list_->GetDisabledExtensions(), " ");
+        JoinString(gpu_driver_bug_list_->GetDisabledExtensions(), ' ');
   }
   gpu::GpuDriverBugList::AppendWorkaroundsFromCommandLine(
       &gpu_driver_bugs_, *base::CommandLine::ForCurrentProcess());
 
   // We have to update GpuFeatureType before notify all the observers.
   NotifyGpuInfoUpdate();
 }
 
 void GpuDataManagerImplPrivate::UpdateGpuInfo(const gpu::GPUInfo& gpu_info) {
   // No further update of gpu_info if falling back to SwiftShader.
@@ skipping 617 matching lines @@
   gpu_info_.context_info_state = gpu::kCollectInfoFatalFailure;
 #if defined(OS_WIN)
   gpu_info_.dx_diagnostics_info_state = gpu::kCollectInfoFatalFailure;
 #endif
   complete_gpu_info_already_requested_ = true;
   // Some observers might be waiting.
   NotifyGpuInfoUpdate();
 }
 
 }  // namespace content