form.elements should not contain image elements

[Ahmad-S792]

form.elements should not contain image elements
https://bugs.webkit.org/show_bug.cgi?id=87834

Reviewed by NOBODY (OOPS!).

This patch aligns WebKit with Web-Spec [1], Blink / Chromium and Gecko / Firefox.

Image elements should not appear in the form.elements as image element is not
mentioned in listed elements of specs.

[1] http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#category-listed

Cherry-pick test: https://chromium.googlesource.com/chromium/src.git/+/5ab9146e05f7e315976e7066b29738dbd6d56f9e

* Source/WebCore/html/HTMLFormControlsCollection.cpp:
(HTMLFormControlsCollection::updateNamedElementCache): Remove 'imageElements' stuff
* LayoutTests/fast/dom/htmlformcontrolscollection-no-img.html: Add Test Case
* LayoutTests/fast/dom/htmlformcontrolscollection-no-img-expected.txt: Add Test Case Expectation
* LayoutTests/fast/forms/form-image-access-by-name-expected.txt: Rebaselined
* LayoutTests/fast/forms/form-image-access-by-name.html: Rebaselined

0a8ca6d

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	🧪 gtk-wk2
	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv	❌ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim	❌ 🧪 mac-wk2-stress
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 9ed1ad9)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	⏳ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	⏳ 🧪 wpe-wk2
✅ 🧪 webkitperl	🧪 ios-wk2	🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	🧪 mac-wk1	⏳ 🧪 gtk-wk2
⏳ 🛠 🧪 jsc	🧪 api-ios	🧪 mac-wk2	⏳ 🧪 api-gtk
⏳ 🛠 🧪 jsc-arm64	✅ 🛠 tv	⏳ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim	❌ 🧪 mac-wk2-stress
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash b3e0386)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	❌ 🧪 gtk-wk2
	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv	❌ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim	❌ 🧪 mac-wk2-stress
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 0a8ca6d)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	🧪 gtk-wk2
	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv	❌ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim	❌ 🧪 mac-wk2-stress
	✅ 🛠 watch
	✅ 🛠 watch-sim