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 build -d` does not report any errors
- [ 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
- [ ] These changes do not require tests because _____

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1 files changed, 11 insertions, 2 deletions

diff --git a/components/script/dom/htmlbuttonelement.rs b/components/script/dom/htmlbuttonelement.rs
index b309da6466a..f266f0236c5 100644..100755
--- a/components/script/dom/htmlbuttonelement.rs
+++ b/components/script/dom/htmlbuttonelement.rs
@@ -21,7 +21,7 @@ use dom::htmlformelement::HTMLFormElement;
 use dom::node::{Node, UnbindContext, document_from_node, window_from_node};
 use dom::nodelist::NodeList;
 use dom::validation::Validatable;
-use dom::validitystate::ValidityState;
+use dom::validitystate::{ValidityState, ValidationFlags};
 use dom::virtualmethods::VirtualMethods;
 use html5ever_atoms::LocalName;
 use std::cell::Cell;
@@ -238,7 +238,16 @@ impl VirtualMethods for HTMLButtonElement {
 
 impl FormControl for HTMLButtonElement {}
 
-impl Validatable for HTMLButtonElement {}
+impl Validatable for HTMLButtonElement {
+    fn is_instance_validatable(&self) -> bool {
+        true
+    }
+    fn validate(&self, validate_flags: ValidationFlags) -> bool {
+        if validate_flags.is_empty() {}
+        // Need more flag check for different validation types later
+        true
+    }
+}
 
 impl Activatable for HTMLButtonElement {
     fn as_element(&self) -> &Element {