Remove Encoding enum variant UTF16

During testing, I could not get UTF16 to work
properly, even on master.
I removed the option to store UTF16 BOM in
EncodingBom.

helix-view/src/document.rs

@@ -120,8 +120,6 @@ pub struct SavePoint {
 #[derive(Debug, Clone)]
 pub enum EncodingBom {
     UTF8,
-    UTF16BE,
-    UTF16LE,
     NoBom(&'static Encoding),
 }
 
@@ -135,8 +133,6 @@ impl EncodingBom {
     fn encoding(&self) -> &'static Encoding {
         match self {
             EncodingBom::UTF8 => encoding::UTF_8,
-            EncodingBom::UTF16BE => encoding::UTF_16BE,
-            EncodingBom::UTF16LE => encoding::UTF_16LE,
             EncodingBom::NoBom(encoding) => encoding,
         }
     }
@@ -146,10 +142,6 @@ impl EncodingBom {
     fn for_bom(encoding: &'static Encoding) -> Self {
         if encoding == encoding::UTF_8 {
             EncodingBom::UTF8
-        } else if encoding == encoding::UTF_16BE {
-            EncodingBom::UTF16BE
-        } else if encoding == encoding::UTF_16LE {
-            EncodingBom::UTF16LE
         } else {
             EncodingBom::NoBom(encoding)
         }
@@ -165,18 +157,6 @@ impl EncodingBom {
                 buf[2] = 0xbf;
                 3
             }
-            EncodingBom::UTF16BE => {
-                buf[0] = 0xfe;
-                buf[1] = 0xff;
-                2
-            }
-
-            EncodingBom::UTF16LE => {
-                buf[0] = 0xef;
-                buf[1] = 0xff;
-                2
-            }
-
             EncodingBom::NoBom(_) => 0,
         }
     }