chore: remove critical circular dependencies (#8114)

* chore: remove critical circular dependencies

* chore: fix tslint errors

* chore: remove platform specific types from interfaces

* chore: update unit tests polyfills

* fix: incorrect null check

* chore: update api.md file

* test: improve test case

* chore: apply comments

* test: avoid page style leaks in tests

nativescript-core/ui/core/bindable/bindable-resources.ts

@@ -0,0 +1,9 @@
+let resources: any = {};
+
+export function get() {
+    return resources;
+}
+
+export function set(res: any) {
+    resources = res;
+}