mime: lists the "common types" listed on MDN

Simply implements the first recommended type for each file extension listed in MDN https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types

However, this excludes ".3gp" and ".3gp2" as from from I can tell it is not possible to know if it is video or audio solely from file extension.

As far as I can tell there are two previous PRs that each implemented a type simply because they were in common use.

Updates golang#69530

src/mime/type.go

@@ -51,22 +51,81 @@ func setMimeTypes(lowerExt, mixExt map[string]string) {
 }
 
 var builtinTypesLower = map[string]string{
-	".avif": "image/avif",
-	".css":  "text/css; charset=utf-8",
-	".gif":  "image/gif",
-	".htm":  "text/html; charset=utf-8",
-	".html": "text/html; charset=utf-8",
-	".jpeg": "image/jpeg",
-	".jpg":  "image/jpeg",
-	".js":   "text/javascript; charset=utf-8",
-	".json": "application/json",
-	".mjs":  "text/javascript; charset=utf-8",
-	".pdf":  "application/pdf",
-	".png":  "image/png",
-	".svg":  "image/svg+xml",
-	".wasm": "application/wasm",
-	".webp": "image/webp",
-	".xml":  "text/xml; charset=utf-8",
+	".7z":     "application/x-7z-compressed",
+	".aac":    "audio/aac",
+	".abw":    "application/x-abiword",
+	".apng":   "image/apng",
+	".arc":    "application/x-freearc",
+	".avi":    "video/x-msvideo",
+	".avif":   "image/avif",
+	".azw":    "application/vnd.amazon.ebook",
+	".bin":    "application/octet-stream",
+	".bmp":    "image/bmp",
+	".bz":     "application/x-bzip",
+	".bz2":    "application/x-bzip2",
+	".cda":    "application/x-cdf",
+	".csh":    "application/x-csh",
+	".css":    "text/css; charset=utf-8",
+	".csv":    "text/csv",
+	".doc":    "application/msword",
+	".docx":   "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+	".eot":    "application/vnd.ms-fontobject",
+	".epub":   "application/epub+zip",
+	".gif":    "image/gif",
+	".gz":     "application/gzip",
+	".htm":    "text/html; charset=utf-8",
+	".html":   "text/html; charset=utf-8",
+	".ico":    "image/vnd.microsoft.icon",
+	".ics":    "text/calendar",
+	".jar":    "application/java-archive",
+	".jpeg":   "image/jpeg",
+	".jpg":    "image/jpeg",
+	".js":     "text/javascript; charset=utf-8",
+	".json":   "application/json",
+	".jsonld": "application/ld+json",
+	".mid":    "audio/midi",
+	".midi":   "audio/midi",
+	".mjs":    "text/javascript; charset=utf-8",
+	".mp3":    "audio/mpeg",
+	".mp4":    "video/mp4",
+	".mpeg":   "video/mpeg",
+	".mpkg":   "application/vnd.apple.installer+xml",
+	".odp":    "application/vnd.oasis.opendocument.presentation",
+	".ods":    "application/vnd.oasis.opendocument.spreadsheet",
+	".odt":    "application/vnd.oasis.opendocument.text",
+	".oga":    "audio/ogg",
+	".ogv":    "video/ogg",
+	".ogx":    "application/ogg",
+	".opus":   "audio/ogg",
+	".otf":    "font/otf",
+	".pdf":    "application/pdf",
+	".png":    "image/png",
+	".ppt":    "application/vnd.ms-powerpoint",
+	".pptx":   "application/vnd.openxmlformats-officedocument.presentationml.presentation",
+	".rar":    "application/vnd.rar",
+	".rtf":    "application/rtf",
+	".sh":     "application/x-sh",
+	".svg":    "image/svg+xml",
+	".tar":    "application/x-tar",
+	".tif":    "image/tiff",
+	".tiff":   "image/tiff",
+	".ts":     "video/mp2t",
+	".ttf":    "font/ttf",
+	".txt":    "text/plain",
+	".vsd":    "application/vnd.visio",
+	".wasm":   "application/wasm",
+	".wav":    "audio/wav",
+	".weba":   "audio/webm",
+	".webm":   "video/webm",
+	".webp":   "image/webp",
+	".woff":   "font/woff",
+	".woff2":  "font/woff2",
+	".xhtml":  "application/xhtml+xml",
+	".xls":    "application/vnd.ms-excel",
+	".xlsx":   "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+	".xml":    "text/xml; charset=utf-8",
+	".xul":    "application/vnd.mozilla.xul+xml",
+	".zip":    "application/zip",
 }
 
 var once sync.Once // guards initMime