Make the error on string continuations a linter-only check

PiperOrigin-RevId: 611469524

Author: lauraharker

src/com/google/javascript/jscomp/DiagnosticGroups.java

@@ -604,7 +604,8 @@ public static DiagnosticGroup forName(String name) {
               ClosureCheckModule.INCORRECT_SHORTNAME_CAPITALIZATION,
               ClosureRewriteModule.USELESS_USE_STRICT_DIRECTIVE,
               RhinoErrorReporter.JSDOC_MISSING_BRACES_WARNING,
-              RhinoErrorReporter.UNNECESSARY_ESCAPE));
+              RhinoErrorReporter.UNNECESSARY_ESCAPE,
+              RhinoErrorReporter.STRING_CONTINUATION));
 
   public static final DiagnosticGroup STRICT_MODULE_CHECKS =
       DiagnosticGroups.registerGroup(

src/com/google/javascript/jscomp/RhinoErrorReporter.java

@@ -101,8 +101,9 @@ class RhinoErrorReporter {
           "JSC_INVALID_OCTAL_LITERAL",
           "This style of octal literal is not supported in strict mode.");
 
+  // This check should only be enabled in the lintChecks DiagnosticGroup as part of the linter
   static final DiagnosticType STRING_CONTINUATION =
-      DiagnosticType.warning("JSC_STRING_CONTINUATION", "{0}");
+      DiagnosticType.disabled("JSC_STRING_CONTINUATION", "{0}");
 
   static final DiagnosticType LANGUAGE_FEATURE =
       DiagnosticType.error("JSC_LANGUAGE_FEATURE", "{0}.");