Fixes #3642: Generate dynamic CSS for decorations also for high contrast

src/vs/editor/browser/services/codeEditorServiceImpl.ts

@@ -107,6 +107,7 @@ class DecorationRenderOptions implements IModelDecorationOptions {
 	public dispose(): void {
 		dom.removeCSSRulesWithPrefix(CSSNameHelper.getDeletionPrefixFor(ThemeType.Light, this._key), this._styleSheet);
 		dom.removeCSSRulesWithPrefix(CSSNameHelper.getDeletionPrefixFor(ThemeType.Dark, this._key), this._styleSheet);
+		dom.removeCSSRulesWithPrefix(CSSNameHelper.getDeletionPrefixFor(ThemeType.HighContrastBlack, this._key), this._styleSheet);
 	}
 
 	private static _CSS_MAP = {
@@ -221,6 +222,7 @@ class DecorationRenderOptions implements IModelDecorationOptions {
 			}
 			if (darkCSS.length > 0) {
 				this._createCSSSelector(styleSheet, ThemeType.Dark, key, ruleType, darkCSS);
+				this._createCSSSelector(styleSheet, ThemeType.HighContrastBlack, key, ruleType, darkCSS);
 			}
 			return CSSNameHelper.getClassName(key, ruleType);
 		}
@@ -234,7 +236,8 @@ class DecorationRenderOptions implements IModelDecorationOptions {
 
 enum ThemeType {
 	Light = 0,
-	Dark = 1
+	Dark = 1,
+	HighContrastBlack = 2
 }
 enum ModelDecorationCSSRuleType {
 	ClassName = 0,
@@ -247,7 +250,10 @@ class CSSNameHelper {
 		if (theme === ThemeType.Light) {
 			return '.monaco-editor.vs';
 		}
-		return '.monaco-editor.vs-dark';
+		if (theme === ThemeType.Dark) {
+			return '.monaco-editor.vs-dark';
+		}
+		return '.monaco-editor.hc-black';
 	}
 
 	public static getClassName(key:string, type:ModelDecorationCSSRuleType): string {