Use armeabi-v7a version code for MozillaOnline builds

app/build.gradle

@@ -264,9 +264,11 @@ android.applicationVariants.all { variant ->
 
         variant.outputs.each { output ->
             def abi = output.getFilter(OutputFile.ABI)
+            // If it is a Mozilla Online build, use a unified version code of armeabi-v7a
+            def arch = (project.hasProperty("mozillaOnline") || gradle.hasProperty("localProperties.mozillaOnline")) ? "armeabi-v7a" : abi
             // We use the same version code generator, that we inherited from Fennec, across all channels - even on
             // channels that never shipped a Fennec build.
-            def versionCodeOverride = Config.generateFennecVersionCode(abi)
+            def versionCodeOverride = Config.generateFennecVersionCode(arch)
 
             println("versionCode for $abi = $versionCodeOverride")