Use art_defaults in libnative*, for consistency.

Also change to //art:__submodules__ for consistent internal visibility, and
some TODO comment corrections.

Test: m WITH_TIDY=1
Test: build & boot
Test: atest art/libnativeloader/test (no new errors, but existing ones on arm64 - b/142896688)
Test: (atest art/libnativebridge/tests doesn't work at all, but that's not new - b/142897320)
Bug: 137364733
Bug: 133140750
Change-Id: If9ddb5a597eea3606342c3625dcdb3bcf5d19041
diff --git a/libnativebridge/native_bridge.cc b/libnativebridge/native_bridge.cc
index 82dd562..6790a18 100644
--- a/libnativebridge/native_bridge.cc
+++ b/libnativebridge/native_bridge.cc
@@ -350,7 +350,7 @@
 }
 
 // Set up the environment for the bridged app.
-static void SetupEnvironment(const NativeBridgeCallbacks* callbacks, JNIEnv* env, const char* isa) {
+static void SetupEnvironment(const NativeBridgeCallbacks* cbs, JNIEnv* env, const char* isa) {
   // Need a JNIEnv* to do anything.
   if (env == nullptr) {
     ALOGW("No JNIEnv* to set up app environment.");
@@ -358,7 +358,7 @@
   }
 
   // Query the bridge for environment values.
-  const struct NativeBridgeRuntimeValues* env_values = callbacks->getAppEnv(isa);
+  const struct NativeBridgeRuntimeValues* env_values = cbs->getAppEnv(isa);
   if (env_values == nullptr) {
     return;
   }