Add a way to send the resource percentage signal to the RC.

components/offline_pages/core/background/BUILD.gn

Index: components/offline_pages/core/background/BUILD.gn
diff --git a/components/offline_pages/core/background/BUILD.gn b/components/offline_pages/core/background/BUILD.gn
index 63971560654a5af112b185e5ac790f8a5d3da05e..b3690a4e88706496e753a5d1f1d43d3b87c5a2d7 100644
--- a/components/offline_pages/core/background/BUILD.gn
+++ b/components/offline_pages/core/background/BUILD.gn
@@ -50,6 +50,8 @@ static_library("background_offliner") {
     "request_queue_store.h",
     "request_queue_store_sql.cc",
     "request_queue_store_sql.h",
+    "resource_data_type.h",
+    "resource_tracker_observer.h",
     "save_page_request.cc",
     "save_page_request.h",
     "scheduler.h",
@@ -63,6 +65,7 @@ static_library("background_offliner") {
     "//components/offline_pages/core",
     "//components/offline_pages/core:switches",
     "//net",
+    "//skia",
     "//sql:sql",
     "//url",
   ]
@@ -79,6 +82,10 @@ static_library("test_support") {
     "request_coordinator_stub_taco.h",
     "request_queue_in_memory_store.cc",
     "request_queue_in_memory_store.h",
+    "resource_data_type.h",
+    "resource_tracker_observer.h",
+    "resource_tracker_observer_stub.cc",
+    "resource_tracker_observer_stub.h",
     "scheduler_stub.cc",
     "scheduler_stub.h",
   ]