Fixed crash if initialization of EGL failed but was tried again later.

The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().

src/main/android/SDL_android_main.c

@@ -0,0 +1,78 @@
+/*
+    SDL_android_main.c, placed in the public domain by Sam Lantinga  3/13/14
+*/
+#include "../../SDL_internal.h"
+
+#ifdef __ANDROID__
+
+/* Include the SDL main definition header */
+#include "SDL_main.h"
+
+/*******************************************************************************
+                 Functions called by JNI
+*******************************************************************************/
+#include <jni.h>
+
+/* Called before SDL_main() to initialize JNI bindings in SDL library */
+extern void SDL_Android_Init(JNIEnv* env, jclass cls);
+
+/* Start up the SDL app */
+int Java_org_libsdl_app_SDLActivity_nativeInit(JNIEnv* env, jclass cls, jobject array)
+{
+    int i;
+    int argc;
+    int status;
+
+    /* This interface could expand with ABI negotiation, callbacks, etc. */
+    SDL_Android_Init(env, cls);
+
+    SDL_SetMainReady();
+
+    /* Prepare the arguments. */
+
+    int len = (*env)->GetArrayLength(env, array);
+    char* argv[1 + len + 1];
+    argc = 0;
+    /* Use the name "app_process" so PHYSFS_platformCalcBaseDir() works.
+       https://bitbucket.org/MartinFelis/love-android-sdl2/issue/23/release-build-crash-on-start
+     */
+    argv[argc++] = SDL_strdup("app_process");
+    for (i = 0; i < len; ++i) {
+        const char* utf;
+        char* arg = NULL;
+        jstring string = (*env)->GetObjectArrayElement(env, array, i);
+        if (string) {
+            utf = (*env)->GetStringUTFChars(env, string, 0);
+            if (utf) {
+                arg = SDL_strdup(utf);
+                (*env)->ReleaseStringUTFChars(env, string, utf);
+            }
+            (*env)->DeleteLocalRef(env, string);
+        }
+        if (!arg) {
+            arg = SDL_strdup("");
+        }
+        argv[argc++] = arg;
+    }
+    argv[argc] = NULL;
+
+
+    /* Run the application. */
+
+    status = SDL_main(argc, argv);
+
+    /* Release the arguments. */
+
+    for (i = 0; i < argc; ++i) {
+        SDL_free(argv[i]);
+    }
+
+    /* Do not issue an exit or the whole application will terminate instead of just the SDL thread */
+    /* exit(status); */
+
+    return status;
+}
+
+#endif /* __ANDROID__ */
+
+/* vi: set ts=4 sw=4 expandtab: */