Allow RemoteConfig to be lazily initialized.

app/src/main/java/org/thoughtcrime/securesms/ApplicationContext.java

@@ -145,10 +145,6 @@ public class ApplicationContext extends MultiDexApplication implements AppForegr
 
     long startTime = System.currentTimeMillis();
 
-    if (RemoteConfig.internalUser()) {
-      Tracer.getInstance().setMaxBufferSize(35_000);
-    }
-
     super.onCreate();
 
     AppStartup.getInstance().addBlocking("sqlcipher-init", () -> {
@@ -183,6 +179,7 @@ public class ApplicationContext extends MultiDexApplication implements AppForegr
                             .addBlocking("remote-config", RemoteConfig::init)
                             .addBlocking("ring-rtc", this::initializeRingRtc)
                             .addBlocking("glide", () -> SignalGlideModule.setRegisterGlideComponents(new SignalGlideComponents()))
+                            .addBlocking("tracer", this::initializeTracer)
                             .addNonBlocking(() -> RegistrationUtil.maybeMarkRegistrationComplete())
                             .addNonBlocking(() -> Glide.get(this))
                             .addNonBlocking(this::cleanAvatarStorage)
@@ -423,6 +420,12 @@ public class ApplicationContext extends MultiDexApplication implements AppForegr
     }
   }
 
+  private void initializeTracer() {
+    if (RemoteConfig.internalUser()) {
+      Tracer.getInstance().setMaxBufferSize(35_000);
+    }
+  }
+
   private void initializePeriodicTasks() {
     RotateSignedPreKeyListener.schedule(this);
     DirectoryRefreshListener.schedule(this);

app/src/main/java/org/thoughtcrime/securesms/util/RemoteConfig.kt

@@ -1,5 +1,6 @@
 package org.thoughtcrime.securesms.util
 
+import androidx.annotation.GuardedBy
 import androidx.annotation.VisibleForTesting
 import androidx.annotation.WorkerThread
 import org.json.JSONException
@@ -19,6 +20,8 @@ import org.thoughtcrime.securesms.util.RemoteConfig.remoteBoolean
 import org.thoughtcrime.securesms.util.RemoteConfig.remoteValue
 import java.io.IOException
 import java.util.TreeMap
+import java.util.concurrent.locks.ReentrantLock
+import kotlin.concurrent.withLock
 import kotlin.math.max
 import kotlin.math.min
 import kotlin.reflect.KProperty
@@ -48,18 +51,27 @@ object RemoteConfig {
   @VisibleForTesting
   val configsByKey: MutableMap<String, Config<*>> = mutableMapOf()
 
+  @GuardedBy("initLock")
+  @Volatile
+  @VisibleForTesting
+  var initialized: Boolean = false
+  private val initLock: ReentrantLock = ReentrantLock()
+
   @JvmStatic
-  @Synchronized
   fun init() {
-    val current = parseStoredConfig(SignalStore.remoteConfig.currentConfig)
-    val pending = parseStoredConfig(SignalStore.remoteConfig.pendingConfig)
-    val changes = computeChanges(current, pending)
+    initLock.withLock {
+      val current = parseStoredConfig(SignalStore.remoteConfig.currentConfig)
+      val pending = parseStoredConfig(SignalStore.remoteConfig.pendingConfig)
+      val changes = computeChanges(current, pending)
 
-    SignalStore.remoteConfig.currentConfig = mapToJson(pending)
-    REMOTE_VALUES.putAll(pending)
-    triggerFlagChangeListeners(changes)
+      SignalStore.remoteConfig.currentConfig = mapToJson(pending)
+      REMOTE_VALUES.putAll(pending)
+      triggerFlagChangeListeners(changes)
 
-    Log.i(TAG, "init() $REMOTE_VALUES")
+      Log.i(TAG, "init() $REMOTE_VALUES")
+
+      initialized = true
+    }
   }
 
   @JvmStatic
@@ -347,6 +359,15 @@ object RemoteConfig {
     val transformer: (Any?) -> T
   ) {
     operator fun getValue(thisRef: Any?, property: KProperty<*>): T {
+      if (!initialized) {
+        Log.w(TAG, "Tried to read $key before initialization. Initializing now.")
+        initLock.withLock {
+          if (!initialized) {
+            init()
+          }
+        }
+      }
+
       return transformer(REMOTE_VALUES[key])
     }
   }

app/src/test/java/org/thoughtcrime/securesms/util/RemoteConfig_StaticValuesTest.kt

@@ -1,5 +1,6 @@
 package org.thoughtcrime.securesms.util
 
+import org.junit.Before
 import org.junit.Test
 import kotlin.reflect.KProperty1
 import kotlin.reflect.KVisibility
@@ -10,6 +11,11 @@ import kotlin.reflect.full.memberProperties
  */
 class RemoteConfig_StaticValuesTest {
 
+  @Before
+  fun setup() {
+    RemoteConfig.initialized = true
+  }
+
   /**
    * This test cycles the REMOTE_VALUES through a bunch of different inputs, then looks at all of the public getters and checks to see if they return different
    * values when the inputs change. If they don't, then it's likely that the getter is returning a static value, which was likely introduced during testing
@@ -34,6 +40,7 @@ class RemoteConfig_StaticValuesTest {
     val configKeys = RemoteConfig.configsByKey.keys
 
     val ignoreList = setOf(
+      "initialized",
       "REMOTE_VALUES",
       "configsByKey",
       "debugMemoryValues",