Removed unsupported exporters from the CodeEditorDemo and VideoDemo and added compiler errors when trying to build on unsupported platforms

examples/GUI/CodeEditorDemo.h

@@ -31,7 +31,7 @@
 
  dependencies:     juce_core, juce_data_structures, juce_events, juce_graphics,
                    juce_gui_basics, juce_gui_extra
- exporters:        xcode_mac, vs2017, linux_make, androidstudio, xcode_iphone
+ exporters:        xcode_mac, vs2017, linux_make, xcode_iphone
 
  moduleFlags:      JUCE_STRICT_REFCOUNTEDPOINTER=1
 
@@ -48,6 +48,10 @@
 
 #include "../Assets/DemoUtilities.h"
 
+#if JUCE_ANDROID
+ #error "This demo is not supported on Android!"
+#endif
+
 //==============================================================================
 class CodeEditorDemo  : public Component,
                         private FilenameComponentListener

examples/GUI/VideoDemo.h

@@ -31,7 +31,7 @@
 
  dependencies:     juce_core, juce_data_structures, juce_events, juce_graphics,
                    juce_gui_basics, juce_gui_extra, juce_video
- exporters:        xcode_mac, vs2017, linux_make, androidstudio, xcode_iphone
+ exporters:        xcode_mac, vs2017, androidstudio, xcode_iphone
 
  moduleFlags:      JUCE_STRICT_REFCOUNTEDPOINTER=1
 
@@ -702,4 +702,6 @@ private:
         updatePositionSliderAndLabel();
     }
 };
+#elif JUCE_LINUX
+ #error "This demo is not supported on Linux!"
 #endif