Get rid of gpu related switches by passing gpu::GpuPreferences via IPC.

gpu/command_buffer/service/gpu_preferences.h

Index: gpu/command_buffer/service/gpu_preferences.h
diff --git a/gpu/command_buffer/service/gpu_preferences.h b/gpu/command_buffer/service/gpu_preferences.h
index 0c6a883979d0c3e7b5cb51f663789e9754fa85b4..60b7702ac3ab4d81e8374ae5dff68e1eb82f5055 100644
--- a/gpu/command_buffer/service/gpu_preferences.h
+++ b/gpu/command_buffer/service/gpu_preferences.h
@@ -66,10 +66,10 @@ struct GPU_EXPORT GpuPreferences {
   bool enforce_gl_minimums = false;
 
   // Sets the total amount of memory that may be allocated for GPU resources
-  size_t force_gpu_mem_available = 0;
+  unsigned int force_gpu_mem_available = 0;
 
   // Sets the maximum size of the in-memory gpu program cache, in kb
-  size_t gpu_program_cache_size = kDefaultMaxProgramCacheMemoryBytes;
+  unsigned int gpu_program_cache_size = kDefaultMaxProgramCacheMemoryBytes;
 
   // Disables the GPU shader on disk cache.
   bool disable_gpu_shader_disk_cache = false;