Fix Package.swift (#6982)

Author: manjanac

FirebaseMLModelDownloader/Sources/UserDefaultsBacked.swift

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import Foundation
+
 private protocol OptionalProtocol {
   var isNil: Bool { get }
 }

Package.swift

@@ -564,6 +564,7 @@ let package = Package(
       name: "FirebaseMLModelDownloader",
       dependencies: [
         "FirebaseCore",
+        "FirebaseInstallations",
       ],
       path: "FirebaseMLModelDownloader/Sources",
       cSettings: [
@@ -576,37 +577,6 @@ let package = Package(
       path: "FirebaseMLModelDownloader/Tests/Unit"
     ),
 
-    .target(
-      name: "FirebaseMessaging",
-      dependencies: [
-        "FirebaseCore",
-        "FirebaseInstanceID",
-        "GoogleUtilities_AppDelegateSwizzler",
-        "GoogleUtilities_Environment",
-        "GoogleUtilities_Reachability",
-        "GoogleUtilities_UserDefaults",
-      ],
-      path: "FirebaseMessaging/Sources",
-      publicHeadersPath: "Public",
-      cSettings: [
-        .headerSearchPath("../../"),
-      ],
-      linkerSettings: [
-        .linkedFramework("SystemConfiguration", .when(platforms: .some([.iOS, .macOS, .tvOS]))),
-      ]
-    ),
-    .testTarget(
-      name: "MessagingUnit",
-      dependencies: ["FirebaseMessaging", "OCMock"],
-      path: "FirebaseMessaging/Tests/UnitTests",
-      exclude: [
-        "FIRMessagingContextManagerServiceTest.m", // TODO: Adapt its NSBundle usage to SPM.
-      ],
-      cSettings: [
-        .headerSearchPath("../../.."),
-      ]
-    ),
-
     .target(
       name: "FirebaseMessaging",
       dependencies: [