FirebaseInstallations import added to Firebase.h (#4908)

* FirebaseInstallations import added to Firebase.h

* Add Installations to Firebase.podspec

Author: maksymmalyhin

CoreOnly/Sources/Firebase.h

@@ -66,6 +66,10 @@ FirebaseAnalytics dependency to your project to ensure Firebase In App Messaging
     #endif
   #endif
 
+  #if __has_include(<FirebaseInstallations/FirebaseInstallations.h>)
+    #import <FirebaseInstallations/FirebaseInstallations.h>
+  #endif
+
   #if __has_include(<FirebaseInstanceID/FirebaseInstanceID.h>)
     #import <FirebaseInstanceID/FirebaseInstanceID.h>
   #endif

Firebase.podspec

@@ -121,6 +121,11 @@ Simplify your app development, grow your user base, and monetize more effectivel
     ss.ios.dependency 'FirebaseInAppMessaging', '~> 7.0.0-beta'
   end
 
+  s.subspec 'Installations' do |ss|
+    ss.dependency 'Firebase/CoreOnly'
+    ss.dependency 'FirebaseInstallations', '~> 7.0.0'
+  end
+
   s.subspec 'Messaging' do |ss|
     ss.dependency 'Firebase/CoreOnly'
     ss.dependency 'FirebaseMessaging', '~> 7.0.0'