[Offline Pages] Add basic evaluation tests and related changes.

chrome/browser/BUILD.gn

Index: chrome/browser/BUILD.gn
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 99a41ebc5975161d9fa554f3dfbe80db1011e530..60da7a0ea812717473fd0a5dc1cc0cf3e7eb9a65 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -3362,6 +3362,8 @@ split_static_library("browser") {
     # Used for testing only, should not be shipped to end users.
     if (!is_official_build) {
       sources += [
+        "android/offline_pages/evaluation/evaluation_test_scheduler.cc",
+        "android/offline_pages/evaluation/evaluation_test_scheduler.h",
         "android/offline_pages/evaluation/offline_page_evaluation_bridge.cc",
         "android/offline_pages/evaluation/offline_page_evaluation_bridge.h",
       ]