remove duplicate methods in impls

Author: emberian

src/libserialize/json.rs

@@ -1312,7 +1312,7 @@ impl ::Decoder for Decoder {
             value => self.expected("number", &value)
         }
     }
-    fn read_f32(&mut self) -> f32 { self.read_f64() as f32 }
+
     fn read_f32(&mut self) -> f32 { self.read_f64() as f32 }
 
     fn read_char(&mut self) -> char {

src/libstd/str.rs

@@ -2664,9 +2664,6 @@ impl<'a> StrSlice<'a> for &'a str {
         return multibyte_char_range_at(*self, i);
     }
 
-    #[inline]
-    fn char_at(&self, i: uint) -> char { self.char_range_at(i).ch }
-
     #[inline]
     fn char_range_at_reverse(&self, start: uint) -> CharRange {
         let mut prev = start;