[theme] remove line highlight css

src/vs/editor/browser/viewParts/currentLineHighlight/currentLineHighlight.css

@@ -9,16 +9,4 @@
 	left: 0;
 	top: 0;
 	box-sizing: border-box;
-}
-
-.monaco-editor.vs .view-overlays .current-line {
-	border: 2px solid #eee;
-}
-
-.monaco-editor.vs-dark .view-overlays .current-line {
-	border: 2px solid #282828;
-}
-
-.monaco-editor.hc-black .view-overlays .current-line {
-	border: 2px solid #f38518;
-}
+}
\ No newline at end of file

src/vs/editor/browser/viewParts/currentLineMarginHighlight/currentLineMarginHighlight.css

@@ -9,16 +9,4 @@
 	left: 0;
 	top: 0;
 	box-sizing: border-box;
-}
-
-.monaco-editor.vs .margin-view-overlays .current-line-margin {
-	border: 2px solid #eee;
-}
-
-.monaco-editor.vs-dark .margin-view-overlays .current-line-margin {
-	border: 2px solid #282828;
-}
-
-.monaco-editor.hc-black .margin-view-overlays .current-line-margin {
-	border: 2px solid #f38518;
-}
+}
\ No newline at end of file