Fixed compilation errors on Fedora and GCC 10.

es-app/src/FileFilterIndex.h

@@ -14,6 +14,7 @@
 #endif
 
 #include <map>
+#include <string>
 #include <vector>
 
 class FileData;

es-app/src/MetaData.h

@@ -15,6 +15,7 @@
 #endif
 
 #include <map>
+#include <string>
 #include <vector>
 
 namespace pugi { class xml_node; }

es-core/src/InputManager.h

@@ -18,6 +18,7 @@
 #endif
 
 #include <map>
+#include <string>
 
 class InputConfig;
 class Window;

es-core/src/PowerSaver.cpp

@@ -15,6 +15,8 @@
 #include <sstream>
 #endif
 
+#include <string>
+
 bool PowerSaver::mState = false;
 bool PowerSaver::mRunningScreensaver = false;
 

es-core/src/Settings.h

@@ -11,6 +11,7 @@
 #define ES_CORE_SETTINGS_H
 
 #include <map>
+#include <string>
 
 //	This is a singleton for storing settings.
 class Settings

es-core/src/Sound.h

@@ -17,6 +17,7 @@
 #include <SDL2/SDL_audio.h>
 #include <map>
 #include <memory>
+#include <string>
 #include <vector>
 
 class ThemeData;