Remove FileError interface

third_party/WebKit/Source/devtools/front_end/devtools.js

Index: third_party/WebKit/Source/devtools/front_end/devtools.js
diff --git a/third_party/WebKit/Source/devtools/front_end/devtools.js b/third_party/WebKit/Source/devtools/front_end/devtools.js
index f3a91417f68c5ed57a954f58d7eafead6c55e625..b96cf0d4becda136b3fc0b8ae05527a4896b972b 100644
--- a/third_party/WebKit/Source/devtools/front_end/devtools.js
+++ b/third_party/WebKit/Source/devtools/front_end/devtools.js
@@ -1000,6 +1000,7 @@ function sanitizeRemoteFrontendUrl()
 
 /**
  * @suppressGlobalPropertiesCheck
+ * @suppress {checkTypes}
  */
 function installBackwardsCompatibility()
 {
@@ -1053,6 +1054,14 @@ function installBackwardsCompatibility()
 
     // Support for legacy (<M49) frontends.
     Event.prototype.deepPath = undefined;
+
+    // Support for legacy (<53) frontends.
+    window.FileError = {
+        NOT_FOUND_ERR: DOMException.NOT_FOUND_ERR,
+        ABORT_ERR: DOMException.ABORT_ERR,
+        INVALID_MODIFICATION_ERR: DOMException.INVALID_MODIFICATION_ERR,
+        NOT_READABLE_ERR: 0  // No matching DOMException, so code will be 0.
+    };
 }
 
 function windowLoaded()