* Move AppPlatform_emscripten to the sdl directory

As pointed out by #82, the behavior before this commit is unintuitive.

platforms/sdl/AppPlatform_emscripten.cpp

@@ -0,0 +1,33 @@
+#include "AppPlatform_emscripten.hpp"
+
+#include <emscripten.h>
+
+#include "common/Utils.hpp"
+
+AppPlatform_emscripten::AppPlatform_emscripten(std::string storageDir, SDL_Window *window)
+    : AppPlatform_sdlbase(storageDir, window)
+{
+}
+
+Texture AppPlatform_emscripten::loadTexture(const std::string& path, bool b)
+{
+	Texture out;
+	out.field_C = 1;
+	out.field_D = 0;
+
+    std::string realPath = getAssetPath(path);
+
+	char *data = emscripten_get_preloaded_image_data(("/" + realPath).c_str(), &out.m_width, &out.m_height);
+	if (data != NULL)
+	{
+		size_t data_size = out.m_width * out.m_height;
+		out.m_pixels = new uint32_t[data_size];
+		memcpy(out.m_pixels, data, data_size * sizeof(uint32_t));
+		free(data);
+		return out;
+	}
+
+    // I don't think this logic makes any sense
+	LOG_E("Couldn't find file: %s", realPath.c_str());
+	return out;
+}