Revert "Introduce extent to ClangToken"

This reverts commit c462892.

This turned out not to be used, and causes trouble with rust-lang#1740.

src/clang.rs

@@ -797,16 +797,13 @@ impl<'a> Drop for RawTokens<'a> {
     }
 }
 
-/// A raw clang token, that exposes only kind, spelling, and extent. This is a
+/// A raw clang token, that exposes only the kind and spelling. This is a
 /// slightly more convenient version of `CXToken` which owns the spelling
-/// string and extent.
+/// string.
 #[derive(Debug)]
 pub struct ClangToken {
     spelling: CXString,
-    /// The extent of the token. This is the same as the relevant member from
-    /// `CXToken`.
-    pub extent: CXSourceRange,
-    /// The kind of the token. This is the same as the relevant member from
+    /// The kind of token, this is the same as the relevant member from
     /// `CXToken`.
     pub kind: CXTokenKind,
 }
@@ -865,12 +862,7 @@ impl<'a> Iterator for ClangTokenIterator<'a> {
         unsafe {
             let kind = clang_getTokenKind(*raw);
             let spelling = clang_getTokenSpelling(self.tu, *raw);
-            let extent = clang_getTokenExtent(self.tu, *raw);
-            Some(ClangToken {
-                kind,
-                extent,
-                spelling,
-            })
+            Some(ClangToken { kind, spelling })
         }
     }
 }