fix some bit-rot in the ios port of sampleapp

samplecode/SampleApp.cpp

Index: samplecode/SampleApp.cpp
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index ed57f114386ba794aa325ef8d26c8cfd25a02940..2c17379f8803d4081036b22011d896e845a6bcb9 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -2381,6 +2381,7 @@ void get_preferred_size(int* x, int* y, int* width, int* height) {
 }
 
 #ifdef SK_BUILD_FOR_IOS
+#include "SkApplication.h"
 IOS_launch_type set_cmd_line_args(int , char *[], const char* resourceDir) {
     SetResourcePath(resourceDir);
     return kApplication__iOSLaunchType;