Fix transparent diagnostics

Author: lnicola

editors/code/src/diagnostics.ts

@@ -15,7 +15,7 @@ export const URI_SCHEME = "rust-analyzer-diagnostics-view";
 export class TextDocumentProvider implements vscode.TextDocumentContentProvider {
     private _onDidChange = new vscode.EventEmitter<vscode.Uri>();
 
-    public constructor(private readonly ctx: Ctx) {}
+    public constructor(private readonly ctx: Ctx) { }
 
     get onDidChange(): vscode.Event<vscode.Uri> {
         return this._onDidChange.event;
@@ -67,7 +67,7 @@ interface AnserStyle {
 export class AnsiDecorationProvider implements vscode.Disposable {
     private _decorationTypes = new Map<AnserStyle, TextEditorDecorationType>();
 
-    public constructor(private readonly ctx: Ctx) {}
+    public constructor(private readonly ctx: Ctx) { }
 
     dispose(): void {
         for (const decorationType of this._decorationTypes.values()) {
@@ -207,11 +207,6 @@ export class AnsiDecorationProvider implements vscode.Disposable {
             }
         }
 
-        const themeColor = AnsiDecorationProvider._anserToThemeColor[color];
-        if (themeColor) {
-            return new ThemeColor("terminal." + themeColor);
-        }
-
-        return undefined;
+        return AnsiDecorationProvider._anserToThemeColor[color];
     }
 }