Remove source line tracking from MediaList and related DevTools code

Source/devtools/protocol.json

 {
     "version": { "major": "1", "minor": "0" },
     "domains": [{
         "domain": "Inspector",
         "hidden": true,
         "types": [],
         "commands": [
             {
                 "name": "enable",
                 "description": "Enables inspector domain notifications."
@@ skipping 2373 matching lines @@
                 ],
                 "description": "CSS property declaration data."
             },
             {
                 "id": "CSSMedia",
                 "type": "object",
                 "properties": [
                     { "name": "text", "type": "string", "description": "Media query text." },
                     { "name": "source", "type": "string", "enum": ["mediaRule", "importRule", "linkedSheet", "inlineSheet"], "description": "Source of the media query: \"mediaRule\" if specified by a @media rule, \"importRule\" if specified by an @import rule, \"linkedSheet\" if specified by a \"media\" attribute in a linked stylesheet's LINK tag, \"inlineSheet\" if specified by a \"media\" attribute in an inline stylesheet's STYLE tag." },
                     { "name": "sourceURL", "type": "string", "optional": true, "description": "URL of the document containing the media query description." },
-                    { "name": "sourceLine", "type": "integer", "optional": true, "description": "Line in the document containing the media query (not defined for the \"linkedSheet\" source)." },
                     { "name": "range", "$ref": "SourceRange", "optional": true, "description": "The associated rule (@media or @import) header range in the enclosing stylesheet (if available)." }
                 ],
                 "description": "CSS media query descriptor."
             },
             {
                 "id": "SelectorProfileEntry",
                 "type": "object",
                 "properties": [
                     { "name": "selector", "type": "string", "description": "CSS selector of the corresponding rule." },
                     { "name": "url", "type": "string", "description": "URL of the resource containing the corresponding rule." },
@@ skipping 1362 matching lines @@
                 ]
             }
         ],
         "events": [
             {
                 "name": "layerTreeDidChange"
             }
         ]
     }]
 }