fix(auth, android): add browser dependency as crash workaround

The reCAPTCHA auth flow requires androidx.browser but it is not specified
as a transitive dependency upstream, so it crashes.

I attempted to use as wide a version range as I felt safe, and provided an
override if you specify "androidxBrowserVersion" in your android/build.gradle
ext config block

Related #4744
Related firebase/firebase-android-sdk#2164

This may be removed when the upstream issue is closed.

Author: mikehardy

packages/auth/android/build.gradle

@@ -81,10 +81,21 @@ repositories {
   jcenter()
 }
 
+def safeExtGet(prop, fallback) {
+    rootProject.ext.has(prop) ? rootProject.ext.get(prop) : fallback
+}
+
+def BROWSER_VERSION = safeExtGet('androidxBrowserVersion', '[1.0.0, 2.0.0)')
+
 dependencies {
   api appProject
   implementation platform("com.google.firebase:firebase-bom:${ReactNative.ext.getVersion("firebase", "bom")}")
   implementation "com.google.firebase:firebase-auth"
+
+  // This is needed for the reCAPTCHA flow but is incorrectly missing as a transitive dependency upstream
+  // https://github.com/invertase/react-native-firebase/issues/4744
+  // https://github.com/firebase/firebase-android-sdk/issues/2164
+  implementation "androidx.browser:browser:${BROWSER_VERSION}"
 }
 
 ReactNative.shared.applyPackageVersion()