Update the documentation to reflect web support (#1183)

* Update the documentation to reflect web support

Indicate which methods have platform-specific web behavior

* cargo fmt

src/platform_impl/web/monitor.rs

@@ -10,19 +10,21 @@ impl Handle {
     }
 
     pub fn position(&self) -> PhysicalPosition {
-        unimplemented!();
+        PhysicalPosition { x: 0.0, y: 0.0 }
     }
 
     pub fn name(&self) -> Option<String> {
-        unimplemented!();
+        None
     }
 
     pub fn size(&self) -> PhysicalSize {
-        unimplemented!();
+        PhysicalSize {
+            width: 0.0,
+            height: 0.0,
+        }
     }
 
     pub fn video_modes(&self) -> impl Iterator<Item = VideoMode> {
-        // TODO: is this possible ?
         std::iter::empty()
     }
 }

src/platform_impl/web/window.rs

@@ -177,13 +177,13 @@ impl Window {
 
     #[inline]
     pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ExternalError> {
-        // TODO: pointer capture
+        // Intentionally a no-op, as the web does not support setting cursor positions
         Ok(())
     }
 
     #[inline]
     pub fn set_cursor_grab(&self, _grab: bool) -> Result<(), ExternalError> {
-        // TODO: pointer capture
+        // Intentionally a no-op, as the web does not (properly) support grabbing the cursor
         Ok(())
     }
 
@@ -199,7 +199,7 @@ impl Window {
 
     #[inline]
     pub fn set_maximized(&self, _maximized: bool) {
-        // TODO: should there be a maximization / fullscreen API?
+        // Intentionally a no-op, as canvases cannot be 'maximized'
     }
 
     #[inline]
@@ -230,7 +230,7 @@ impl Window {
 
     #[inline]
     pub fn set_ime_position(&self, _position: LogicalPosition) {
-        // TODO: what is this?
+        // Currently a no-op as it does not seem there is good support for this on web
     }
 
     #[inline]