[core] fix(HTMLSelect): align right icon with button (#6275)

packages/core/src/components/html-select/_common.scss

@@ -12,7 +12,7 @@
   -webkit-appearance: none;
   border-radius: $pt-border-radius;
   height: $pt-button-height;
-  padding: 0 ($input-padding-horizontal * 2.5) 0 $input-padding-horizontal;
+  padding: 0 ($input-padding-horizontal * 3) 0 $input-padding-horizontal;
   // fill parent container
   width: 100%;
   /* stylelint-enable property-no-vendor-prefix */
@@ -39,11 +39,13 @@
   cursor: not-allowed;
 }
 
-%pt-select-arrow {
+%pt-select-icon {
   color: $pt-icon-color;
   pointer-events: none;
   position: absolute;
-  right: $input-padding-horizontal * 0.7;
+  // N.B. it's more important for the icon to vertically align with button right icons rather than
+  // input right padding, see https://github.com/palantir/blueprint/issues/6184
+  right: $pt-grid-size;
   top: ($pt-button-height - $pt-icon-size-standard) * 0.5;
 
   &.#{$ns}-disabled {

packages/core/src/components/html-select/_html-select.scss

@@ -41,15 +41,10 @@ Styleguide select
     &:disabled {
       @extend %pt-select-disabled;
     }
-
-    &::-ms-expand {
-      // IE11 styling to hide the arrow
-      display: none;
-    }
   }
 
   .#{$ns}-icon {
-    @extend %pt-select-arrow;
+    @extend %pt-select-icon;
     @include pt-icon-colors();
   }
 
@@ -98,14 +93,14 @@ Styleguide select
 
 .#{$ns}-html-select {
   .#{$ns}-icon {
-    @extend %pt-select-arrow;
+    @extend %pt-select-icon;
   }
 }
 
 // N.B. this icon implementation is deprecated and will be removed in Blueprint 6.0
 .#{$ns}-select {
   &::after {
-    @extend %pt-select-arrow;
+    @extend %pt-select-icon;
     @include pt-icon();
     content: map-get($blueprint-icon-codepoints, "double-caret-vertical");
   }