Revert "Use the platform SDK version from the config."

This reverts commit 9bef52380933a3f1444607739d94a98506e0b441.

Reason for revert: Broke things

Change-Id: Ic3deac4fb6992572ac0cc95fa04d003e0c29f113
diff --git a/cc/ndk_library.go b/cc/ndk_library.go
index 94be17c..48fbf4d 100644
--- a/cc/ndk_library.go
+++ b/cc/ndk_library.go
@@ -139,7 +139,16 @@
 }
 
 func generateStubApiVariants(mctx android.BottomUpMutatorContext, c *stubDecorator) {
-	maxVersion := mctx.AConfig().PlatformSdkVersionInt()
+	// TODO(danalbert): Use PlatformSdkVersion when possible.
+	// This is an interesting case because for the moment we actually need 24
+	// even though the latest released version in aosp is 23. prebuilts/ndk/r11
+	// has android-24 versions of libraries, and as platform libraries get
+	// migrated the libraries in prebuilts will need to depend on them.
+	//
+	// Once everything is all moved over to the new stuff (when there isn't a
+	// prebuilts/ndk any more) then this should be fixable, but for now I think
+	// it needs to remain as-is.
+	maxVersion := 24
 
 	firstVersion, err := normalizeNdkApiLevel(c.properties.First_version,
 		mctx.Arch())