Fix webview building with webview_includes_weblayer = false

The components scaled resources were added in
http://crrev.com/c/2250920, and are only needed for WebLayer.

Bug: 1023811
Change-Id: I58d9b8aa331e6a102bc9b97367d095f0bd7ed089
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2258686
Auto-Submit: Clark DuVall <cduvall@chromium.org>
Commit-Queue: Richard Coles <torne@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#781329}

android_webview/BUILD.gn

@@ -754,10 +754,8 @@ repack("repack_100_percent") {
     "$root_gen_dir/content/app/resources/content_resources_100_percent.pak",
     "$root_gen_dir/third_party/blink/public/resources/blink_scaled_resources_100_percent.pak",
     "$root_gen_dir/ui/resources/ui_resources_100_percent.pak",
-    "$target_gen_dir/components_resources_100_percent.pak",
   ]
   deps = [
-    ":generate_components_scaled_resources",
     "//content/app/resources",
     "//third_party/blink/public:scaled_resources_100_percent",
     "//ui/resources",
@@ -768,6 +766,10 @@ repack("repack_100_percent") {
     repack_whitelist = system_webview_pak_whitelist
     deps += [ ":system_webview_pak_whitelist" ]
   }
+  if (webview_includes_weblayer) {
+    sources += [ "$target_gen_dir/components_resources_100_percent.pak" ]
+    deps += [ ":generate_components_scaled_resources" ]
+  }
 }
 
 android_assets("pak_file_assets") {