Fix fiam vendoring issue.

It looks like AGP has stopped "transforming" test classes, so switching
to Provider instead of `dagger.Lazy` to avoid the problem. It's not an
issue since the injected class is has FirebaseAppScope(which is
singleton-like).

Author: vkryachko

firebase-inappmessaging/src/androidTest/java/com/google/firebase/inappmessaging/TestApiClientModule.java

@@ -26,9 +26,9 @@
 import com.google.firebase.inappmessaging.internal.injection.scopes.FirebaseAppScope;
 import com.google.firebase.inappmessaging.internal.time.Clock;
 import com.google.firebase.installations.FirebaseInstallationsApi;
-import dagger.Lazy;
 import dagger.Module;
 import dagger.Provides;
+import javax.inject.Provider;
 import javax.inject.Singleton;
 
 /** Test bindings for API client */
@@ -77,7 +77,9 @@ TestDeviceHelper providesTestDeviceHelper() {
   @Provides
   @FirebaseAppScope
   ApiClient providesApiClient(
-      Lazy<GrpcClient> grpcClient, Application application, ProviderInstaller providerInstaller) {
+      Provider<GrpcClient> grpcClient,
+      Application application,
+      ProviderInstaller providerInstaller) {
     return new ApiClient(grpcClient, firebaseApp, application, clock, providerInstaller);
   }
 }

firebase-inappmessaging/src/main/java/com/google/firebase/inappmessaging/internal/ApiClient.java

@@ -27,11 +27,11 @@
 import com.google.internal.firebase.inappmessaging.v1.sdkserving.ClientAppInfo;
 import com.google.internal.firebase.inappmessaging.v1.sdkserving.FetchEligibleCampaignsRequest;
 import com.google.internal.firebase.inappmessaging.v1.sdkserving.FetchEligibleCampaignsResponse;
-import dagger.Lazy;
 import java.util.Locale;
 import java.util.TimeZone;
 import java.util.concurrent.TimeUnit;
 import javax.annotation.Nullable;
+import javax.inject.Provider;
 
 /**
  * Interface to speak to the fiam backend
@@ -43,14 +43,14 @@ public class ApiClient {
 
   private static final String FETCHING_CAMPAIGN_MESSAGE = "Fetching campaigns from service.";
 
-  private final Lazy<GrpcClient> grpcClient;
+  private final Provider<GrpcClient> grpcClient;
   private final FirebaseApp firebaseApp;
   private final Application application;
   private final Clock clock;
   private final ProviderInstaller providerInstaller;
 
   public ApiClient(
-      Lazy<GrpcClient> grpcClient,
+      Provider<GrpcClient> grpcClient,
       FirebaseApp firebaseApp,
       Application application,
       Clock clock,

firebase-inappmessaging/src/main/java/com/google/firebase/inappmessaging/internal/injection/modules/ApiClientModule.java

@@ -26,9 +26,9 @@
 import com.google.firebase.inappmessaging.internal.injection.scopes.FirebaseAppScope;
 import com.google.firebase.inappmessaging.internal.time.Clock;
 import com.google.firebase.installations.FirebaseInstallationsApi;
-import dagger.Lazy;
 import dagger.Module;
 import dagger.Provides;
+import javax.inject.Provider;
 
 /**
  * Provider for ApiClient
@@ -77,7 +77,9 @@ TestDeviceHelper providesTestDeviceHelper(SharedPreferencesUtils sharedPreferenc
   @Provides
   @FirebaseAppScope
   ApiClient providesApiClient(
-      Lazy<GrpcClient> grpcClient, Application application, ProviderInstaller providerInstaller) {
+      Provider<GrpcClient> grpcClient,
+      Application application,
+      ProviderInstaller providerInstaller) {
     return new ApiClient(grpcClient, firebaseApp, application, clock, providerInstaller);
   }
 }