Add the component build for AppRegistryCache.

Convert source_set to component for "app_update", because
AppRegistryCache is used by Ash, which uses component. So modify
"app_update" as component too to avoid the multiple instance issue for
AppRegistryCache in component build.

BUG=1124863

Change-Id: Ic90a78b7314616326051b37bfc77d59e9299e124
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2392033Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804637}

components/services/app_service/public/cpp/BUILD.gn

@@ -16,7 +16,8 @@ source_set("app_file_handling") {
   ]
 }
 
-source_set("app_update") {
+component("app_update") {
+  output_name = "APP_UPDATE"
   sources = [
     "app_registry_cache.cc",
     "app_registry_cache.h",
@@ -26,6 +27,8 @@ source_set("app_update") {
     "app_update.h",
   ]
 
+  defines = [ "IS_APP_UPDATE_IMPL" ]
+
   public_deps = [
     "//components/account_id:account_id",
     "//components/services/app_service/public/mojom",

components/services/app_service/public/cpp/app_registry_cache.h

@@ -8,6 +8,7 @@
 #include <map>
 #include <vector>
 
+#include "base/component_export.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "base/observer_list_types.h"
@@ -31,9 +32,9 @@ namespace apps {
 // This class is not thread-safe.
 //
 // See //components/services/app_service/README.md for more details.
-class AppRegistryCache {
+class COMPONENT_EXPORT(APP_UPDATE) AppRegistryCache {
  public:
-  class Observer : public base::CheckedObserver {
+  class COMPONENT_EXPORT(APP_UPDATE) Observer : public base::CheckedObserver {
    public:
     // The apps::AppUpdate argument shouldn't be accessed after OnAppUpdate
     // returns.

components/services/app_service/public/cpp/app_registry_cache_wrapper.h

@@ -7,6 +7,8 @@
 
 #include <map>
 
+#include "base/component_export.h"
+
 class AccountId;
 
 namespace apps {
@@ -15,7 +17,7 @@ class AppRegistryCache;
 
 // Wraps AppRegistryCache to get all AppRegistryCaches independently. Provides
 // the method to get the AppRegistryCache per |account_id|.
-class AppRegistryCacheWrapper {
+class COMPONENT_EXPORT(APP_UPDATE) AppRegistryCacheWrapper {
  public:
   // Returns the global AppRegistryCacheWrapper object.
   static AppRegistryCacheWrapper& Get();

components/services/app_service/public/cpp/app_update.h

@@ -8,6 +8,7 @@
 #include <string>
 #include <vector>
 
+#include "base/component_export.h"
 #include "base/macros.h"
 #include "components/account_id/account_id.h"
 #include "components/services/app_service/public/mojom/types.mojom.h"
@@ -42,7 +43,7 @@ namespace apps {
 // remain valid for the lifetime of the AppUpdate.
 //
 // See //components/services/app_service/README.md for more details.
-class AppUpdate {
+class COMPONENT_EXPORT(APP_UPDATE) AppUpdate {
  public:
   // Modifies |state| by copying over all of |delta|'s known fields: those
   // fields whose values aren't "unknown". The |state| may not be nullptr.