Renamed InvalidData to InvalidOutput

Following some bikeshedding on PR rust-lang#25246.

Author: mzabaluev

src/libstd/ffi/c_str.rs

@@ -238,7 +238,7 @@ impl fmt::Display for NulError {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl From<NulError> for io::Error {
     fn from(_: NulError) -> io::Error {
-        io::Error::new(io::ErrorKind::InvalidData,
+        io::Error::new(io::ErrorKind::InvalidOutput,
                        "data provided contains a nul byte")
     }
 }

src/libstd/io/error.rs

@@ -95,9 +95,9 @@ pub enum ErrorKind {
     /// A parameter was incorrect.
     #[stable(feature = "rust1", since = "1.0.0")]
     InvalidInput,
-    /// Invalid data encountered.
+    /// The operation retrieved invalid data.
     #[stable(feature = "rust1", since = "1.0.0")]
-    InvalidData,
+    InvalidOutput,
     /// The I/O operation's timeout expired, causing it to be canceled.
     #[stable(feature = "rust1", since = "1.0.0")]
     TimedOut,

src/libstd/io/mod.rs

@@ -81,7 +81,7 @@ fn append_to_string<F>(buf: &mut String, f: F) -> Result<usize>
         let ret = f(g.s);
         if str::from_utf8(&g.s[g.len..]).is_err() {
             ret.and_then(|_| {
-                Err(Error::new(ErrorKind::InvalidData,
+                Err(Error::new(ErrorKind::InvalidOutput,
                                "stream did not contain valid UTF-8"))
             })
         } else {

src/libstd/sys/windows/stdio.rs

@@ -170,5 +170,5 @@ impl Output {
 }
 
 fn invalid_encoding() -> io::Error {
-    io::Error::new(io::ErrorKind::InvalidData, "text was not valid unicode")
+    io::Error::new(io::ErrorKind::InvalidOutput, "text was not valid unicode")
 }