[Invalidation] Put test templates into invalidation namespace

This CL puts content of invalidation_service_test_template into
invalidation namespace (before global and "internal" namespace were
used. It allows to avoid multiple "invalidation::" occurencies.

Although test templates are not linked into prod code, it seems safe to
keep them in invalidation namespace (and safer than keeping them in
global namespace as before this CL).

Bug: 1031125
Change-Id: I93543c33919b7f16a76ff33a3f1afce9690eb620
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2627860Reviewed-by: Marc Treib <treib@chromium.org>
Commit-Queue: Maksim Moskvitin <mmoskvitin@google.com>
Cr-Commit-Position: refs/heads/master@{#844051}

components/invalidation/impl/invalidation_service_test_template.cc

@@ -4,24 +4,23 @@
 
 #include "components/invalidation/impl/invalidation_service_test_template.h"
 
-namespace internal {
+namespace invalidation {
 
 BoundFakeInvalidationHandler::BoundFakeInvalidationHandler(
-    const invalidation::InvalidationService& invalidator)
+    const InvalidationService& invalidator)
     : invalidator_(invalidator),
-      last_retrieved_state_(invalidation::DEFAULT_INVALIDATION_ERROR) {}
+      last_retrieved_state_(DEFAULT_INVALIDATION_ERROR) {}
 
 BoundFakeInvalidationHandler::~BoundFakeInvalidationHandler() = default;
 
-invalidation::InvalidatorState
-BoundFakeInvalidationHandler::GetLastRetrievedState() const {
+InvalidatorState BoundFakeInvalidationHandler::GetLastRetrievedState() const {
   return last_retrieved_state_;
 }
 
 void BoundFakeInvalidationHandler::OnInvalidatorStateChange(
-    invalidation::InvalidatorState state) {
+    InvalidatorState state) {
   FakeInvalidationHandler::OnInvalidatorStateChange(state);
   last_retrieved_state_ = invalidator_.GetInvalidatorState();
 }
 
-}  // namespace internal
+}  // namespace invalidation