Add BACKGROUND dump mode to various GPU/CC MemoryDumpProviders

cc/tiles/software_image_decode_controller.h

Index: cc/tiles/software_image_decode_controller.h
diff --git a/cc/tiles/software_image_decode_controller.h b/cc/tiles/software_image_decode_controller.h
index e1427c71e215919d876b75b847a2ee9ee8c2d9f7..f801ffc21c97665d37e428110295dddf2ab8597e 100644
--- a/cc/tiles/software_image_decode_controller.h
+++ b/cc/tiles/software_image_decode_controller.h
@@ -198,10 +198,9 @@ class CC_EXPORT SoftwareImageDecodeController
     void SubtractUsage(size_t usage);
     void ResetUsage();
     size_t total_limit_bytes() const { return limit_bytes_; }
-
-   private:
     size_t GetCurrentUsageSafe() const;
 
+   private:
     size_t limit_bytes_;
     base::CheckedNumeric<size_t> current_usage_bytes_;
   };