Auto merge of #13969 - bbansalWolfPack:master, r=jdm

html form validation initial steps with  test html file

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Added code for initial steps in html form validation.
1. Added methods for trait validatable
2. implemented stub methods for  elements like HTMLInputElement, HTMLButtonElement, etc

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- [ X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
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1 files changed, 5 insertions, 1 deletions

diff --git a/components/script/dom/validation.rs b/components/script/dom/validation.rs
index e9a6a156848..7ba915092a2 100644..100755
--- a/components/script/dom/validation.rs
+++ b/components/script/dom/validation.rs
@@ -1,5 +1,9 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+use dom::validitystate::ValidationFlags;
 
-pub trait Validatable {}
+pub trait Validatable {
+    fn is_instance_validatable(&self) -> bool { true }
+    fn validate(&self, _validate_flags: ValidationFlags) -> bool { true }
+}