Bug 1581979 - Use -SNAPSHOT versions locally to enable the local GeckoView substitution flow. r=nalexander

Differential Revision: https://phabricator.services.mozilla.com/D46235

--HG--
extra : moz-landing-system : lando

mobile/android/geckoview/build.gradle

@@ -359,6 +359,10 @@ android.libraryVariants.all { variant ->
 apply plugin: 'maven-publish'
 
 version = computeVersionNumber()
+if (!mozconfig.substs.MOZILLA_OFFICIAL && !mozconfig.substs.MOZ_ANDROID_FAT_AAR_ARCHITECTURES) {
+    // Use -SNAPSHOT versions locally to enable the local GeckoView substitution flow.
+    version = "${version}-SNAPSHOT"
+}
 
 publishing {
     publications {

substitute-local-geckoview.gradle

@@ -118,6 +118,7 @@ configurations.all { config ->
                         // timestamp already, but let's try to avoid some class of cache
                         // invalidation error while we're here.
                         strategy.cacheDynamicVersionsFor 0, 'seconds'
+                        strategy.cacheChangingModulesFor 0, 'seconds'
                     }
                 }
             }