gpu: Fix dependency cycle between service_sources and config_sources.

gpu/command_buffer/service/gpu_switches.cc

Index: gpu/command_buffer/service/gpu_switches.cc
diff --git a/gpu/command_buffer/service/gpu_switches.cc b/gpu/command_buffer/service/gpu_switches.cc
index 2e4e083353e1e652565d1db9139e99a83428ddb7..d2ca49018b76946986abd318e78757f758a16cd4 100644
--- a/gpu/command_buffer/service/gpu_switches.cc
+++ b/gpu/command_buffer/service/gpu_switches.cc
@@ -3,7 +3,8 @@
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/gpu_switches.h"
-#include "base/basictypes.h"
+
+#include "base/macros.h"
 
 namespace switches {
 
@@ -43,9 +44,6 @@ const char kEnforceGLMinimums[]             = "enforce-gl-minimums";
 // Sets the total amount of memory that may be allocated for GPU resources
 const char kForceGpuMemAvailableMb[]        = "force-gpu-mem-available-mb";
 
-// Pass a set of GpuDriverBugWorkaroundType ids, seperated by ','.
-const char kGpuDriverBugWorkarounds[] = "gpu-driver-bug-workarounds";
-
 // Sets the maximum size of the in-memory gpu program cache, in kb
 const char kGpuProgramCacheSizeKb[]         = "gpu-program-cache-size-kb";