Auto merge of #7764 - j3parker:input-caret-only-for-text, r=pcwalton

Only display text carets in text inputs

For #7756

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tests/ref/basic.list

@@ -337,6 +337,7 @@ device-pixel-ratio=2 != pixel_snapping_border_a.html pixel_snapping_border_ref.h
 == stacking_context_overflow_a.html stacking_context_overflow_ref.html
 == stacking_context_overflow_relative_outline_a.html stacking_context_overflow_relative_outline_ref.html
 == style_is_in_doc.html style_is_in_doc_ref.html
+== submit_focus_a.html submit_focus_b.html
 == table_auto_width.html table_auto_width_ref.html
 == table_caption_bottom_a.html table_caption_bottom_ref.html
 == table_caption_top_a.html table_caption_top_ref.html

tests/ref/submit_focus_a.html

@@ -0,0 +1,10 @@
+<style>
+button {
+    display: inline-block;
+}
+</style>
+<button id="1">Submit</button>
+<script>
+var elem = document.getElementById('1');
+elem.focus();
+</script>

tests/ref/submit_focus_b.html

@@ -0,0 +1,11 @@
+<style>
+input {
+    padding-left: 0;
+    padding-right: 0;
+}
+</style>
+<input id="1" type="submit"></input>
+<script>
+var elem = document.getElementById('1');
+elem.focus();
+</script>