Remove explicit static constructors

Explicit static cctors cause the C# compiler to not mark types as
beforefieldinit, which means the JIT will add checks to each static
method and instance constructors of the type to make sure that the
static constructor was previously called. This can be avoided by
removing explicit static constructors and initializing static fields
inline.

Author: justinvp

src/Microsoft.Net.Http.Headers/HttpRuleParser.cs

@@ -10,7 +10,7 @@ namespace Microsoft.Net.Http.Headers
 {
     internal static class HttpRuleParser
     {
-        private static readonly bool[] TokenChars;
+        private static readonly bool[] TokenChars = CreateTokenChars();
         private const int MaxNestedCount = 5;
         private static readonly string[] DateFormats = new string[] {
             // "r", // RFC 1123, required output format but too strict for input
@@ -43,36 +43,38 @@ internal static class HttpRuleParser
         // iso-8859-1, Western European (ISO)
         internal static readonly Encoding DefaultHttpEncoding = Encoding.GetEncoding("iso-8859-1");
 
-        static HttpRuleParser()
+        private static bool[] CreateTokenChars()
         {
             // token = 1*<any CHAR except CTLs or separators>
             // CTL = <any US-ASCII control character (octets 0 - 31) and DEL (127)>
 
-            TokenChars = new bool[128]; // everything is false
+            var tokenChars = new bool[128]; // everything is false
 
             for (int i = 33; i < 127; i++) // skip Space (32) & DEL (127)
             {
-                TokenChars[i] = true;
+                tokenChars[i] = true;
             }
 
             // remove separators: these are not valid token characters
-            TokenChars[(byte)'('] = false;
-            TokenChars[(byte)')'] = false;
-            TokenChars[(byte)'<'] = false;
-            TokenChars[(byte)'>'] = false;
-            TokenChars[(byte)'@'] = false;
-            TokenChars[(byte)','] = false;
-            TokenChars[(byte)';'] = false;
-            TokenChars[(byte)':'] = false;
-            TokenChars[(byte)'\\'] = false;
-            TokenChars[(byte)'"'] = false;
-            TokenChars[(byte)'/'] = false;
-            TokenChars[(byte)'['] = false;
-            TokenChars[(byte)']'] = false;
-            TokenChars[(byte)'?'] = false;
-            TokenChars[(byte)'='] = false;
-            TokenChars[(byte)'{'] = false;
-            TokenChars[(byte)'}'] = false;
+            tokenChars[(byte)'('] = false;
+            tokenChars[(byte)')'] = false;
+            tokenChars[(byte)'<'] = false;
+            tokenChars[(byte)'>'] = false;
+            tokenChars[(byte)'@'] = false;
+            tokenChars[(byte)','] = false;
+            tokenChars[(byte)';'] = false;
+            tokenChars[(byte)':'] = false;
+            tokenChars[(byte)'\\'] = false;
+            tokenChars[(byte)'"'] = false;
+            tokenChars[(byte)'/'] = false;
+            tokenChars[(byte)'['] = false;
+            tokenChars[(byte)']'] = false;
+            tokenChars[(byte)'?'] = false;
+            tokenChars[(byte)'='] = false;
+            tokenChars[(byte)'{'] = false;
+            tokenChars[(byte)'}'] = false;
+
+            return tokenChars;
         }
 
         internal static bool IsTokenChar(char character)