Bug 1793700 - follow-up: Make color control styling match Chromium. r=TYLin

The previous patch made me realize that we have this widget-imposed size
for color controls which doesn't match any other browser. This patch
removes it.

I don't feel strongly whether we should land this other than "it matches
other browsers, and removes a special case from Gecko". Behavior might
be simpler to understand for authors this way.

Differential Revision: https://phabricator.services.mozilla.com/D158620

layout/reftests/forms/input/color/reference-style.css

@@ -8,14 +8,10 @@ div.input-color-swatch {
   border: 1px solid grey;
   display: block;
   background-color: #000000; /* default color for input type color */
-  height: 20px; /* for a real ::-moz-color-swatch, its 100% height computes to
-                    the widget-supplied min-height (32px) minus padding
-                    (4px each side) minus border (2px each side) */
 }
 
 button.input-color {
   width: 64px;
-  height: 23px;
-  min-height: 32px; /* widget-supplied min-height */
+  height: 32px;
   padding: 4px; /* widget-supplied padding */
 }

layout/reftests/writing-mode/ua-style-sheet-input-color-1-ref.html

@@ -15,12 +15,12 @@ input[type=color] {
 .ltr input[type="color"],
 .rtl input[type="color"] {
   width: 64px;
-  height: 23px;
+  height: 32px;
 }
 
 .v-rl input[type="color"] {
   height: 64px;
-  width: 23px;
+  width: 32px;
 }
 </style>
 <div class=ltr>

layout/style/res/forms.css

@@ -523,7 +523,7 @@ input:is([type=reset], [type=button], [type=submit]) {
 
 input[type=color] {
   inline-size: 64px;
-  block-size: 23px;
+  block-size: 32px;
 }
 
 @media (-moz-non-native-content-theme) {

widget/Theme.cpp

@@ -72,7 +72,6 @@ static constexpr gfx::sRGBColor sColorMeterRed10(
 static constexpr gfx::sRGBColor sColorMeterRed20(
     gfx::sRGBColor::UnusualFromARGB(0xff810220));
 
-static const CSSCoord kMinimumColorPickerHeight = 32.0f;
 static const CSSCoord kMinimumRangeThumbSize = 20.0f;
 static const CSSCoord kMinimumDropdownArrowButtonWidth = 18.0f;
 static const CSSCoord kMinimumSpinnerButtonWidth = 18.0f;
@@ -1516,11 +1515,6 @@ LayoutDeviceIntSize Theme::GetMinimumWidgetSize(nsPresContext* aPresContext,
 
   LayoutDeviceIntSize result;
   switch (aAppearance) {
-    case StyleAppearance::Button:
-      if (aFrame->IsColorControlFrame()) {
-        result.height = (kMinimumColorPickerHeight * dpiRatio).Rounded();
-      }
-      break;
     case StyleAppearance::RangeThumb:
       result.SizeTo((kMinimumRangeThumbSize * dpiRatio).Rounded(),
                     (kMinimumRangeThumbSize * dpiRatio).Rounded());