Fixed bug 3917 - Android, issues with getManifestEnvironmentVariable

Sylvain

Some issue with this commit:
https://hg.libsdl.org/SDL/rev/97387a8b88d3

There is a memory allocation missing.

src/core/android/SDL_android.c

@@ -2121,6 +2121,7 @@ char *SDL_AndroidGetManifestEnvironmentVariable(const char *variableName)
 
     jstring jVariableName = (*env)->NewStringUTF(env, variableName);
     jstring jResult = (jstring)((*env)->CallStaticObjectMethod(env, mActivityClass, midGetManifestEnvironmentVariable, jVariableName));
+    (*env)->DeleteLocalRef(env, jVariableName);
 
     if (jResult == NULL) {
         return NULL;