Use mojo for WebappRegistry.

chrome/android/BUILD.gn

Index: chrome/android/BUILD.gn
diff --git a/chrome/android/BUILD.gn b/chrome/android/BUILD.gn
index b9e6736fdaa07afab42b9540f6a416cdaa1fc1a8..1a538d4bbbbc53c9adaa36a946094484cfd60053 100644
--- a/chrome/android/BUILD.gn
+++ b/chrome/android/BUILD.gn
@@ -148,6 +148,7 @@ android_library("chrome_java") {
     "//base:base_java",
     "//chrome/android/webapk/libs/client:client_java",
     "//chrome/android/webapk/libs/common:common_java",
+    "//chrome/browser:webapp_registry_mojom_java",
     "//components/safe_json/android:safe_json_java",
     "//components/variations/android:variations_java",
     "//components/web_contents_delegate_android:web_contents_delegate_android_java",
@@ -308,6 +309,7 @@ junit_binary("chrome_junit_tests") {
     "//base:base_java",
     "//base:base_java_test_support",
     "//base:base_junit_test_support",
+    "//chrome/browser:webapp_registry_mojom_java",
     "//components/bookmarks/common/android:bookmarks_java",
     "//components/invalidation/impl:java",
     "//components/sync:sync_java_test_support",
@@ -315,6 +317,8 @@ junit_binary("chrome_junit_tests") {
     "//components/web_restrictions:web_restrictions_java",
     "//content/public/android:content_java",
     "//device/geolocation:geolocation_java",
+    "//mojo/public/java:bindings",
+    "//mojo/public/java:system",
     "//net/android:net_java",
     "//third_party/WebKit/public:blink_headers_java",
     "//third_party/android_tools:android_support_v7_mediarouter_java",
@@ -361,6 +365,7 @@ android_library("chrome_test_java") {
     "//base:base_java_test_support",
     "//chrome/android:chrome_java",
     "//chrome/android/webapk/libs/common:common_java",
+    "//chrome/browser:webapp_registry_mojom_java",
     "//chrome/test/android:chrome_java_test_support",
     "//components/bookmarks/common/android:bookmarks_java",
     "//components/dom_distiller/android:dom_distiller_core_java",