Build/Test Tools: Update the `caniuse` browser data and regenerate CSS.

This includes three minor updates to generated CSS files:

- A single `-webkit-` prefix is removed for `min-width`, which was required for Safari <= 10.1 (0.06% total global usage). WordPress only supports the last two versions.
- 2 instances where the `-o-` prefix are added for `tab-size`. This appears to be for Opera Mobile, which has creeped back over the 1% global usage.

Props peterwilsoncc, jorbin.
Fixes #53686.
Built from https://develop.svn.wordpress.org/trunk@51456


git-svn-id: http://core.svn.wordpress.org/trunk@51067 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/css/common-rtl.css

@@ -3154,6 +3154,7 @@ img {
 	font-size: 13px;
 	background: #f6f7f7;
 	-moz-tab-size: 4;
+	-o-tab-size: 4;
 	tab-size: 4;
 }
 

wp-admin/css/common.css

@@ -3153,6 +3153,7 @@ img {
 	font-size: 13px;
 	background: #f6f7f7;
 	-moz-tab-size: 4;
+	-o-tab-size: 4;
 	tab-size: 4;
 }
 

wp-admin/css/customize-controls-rtl.css

@@ -1579,6 +1579,7 @@ p.customize-section-description {
 	font-size: 12px;
 	padding: 6px 8px;
 	-moz-tab-size: 2;
+	-o-tab-size: 2;
 	tab-size: 2;
 }
 .customize-control-code_editor textarea,

wp-admin/css/customize-controls.css

@@ -1578,6 +1578,7 @@ p.customize-section-description {
 	font-size: 12px;
 	padding: 6px 8px;
 	-moz-tab-size: 2;
+	-o-tab-size: 2;
 	tab-size: 2;
 }
 .customize-control-code_editor textarea,

wp-includes/css/admin-bar-rtl.css

@@ -989,7 +989,6 @@ html:lang(he-il) .rtl #wpadminbar * {
 	/* Override default min-width so dropdown lists aren't stretched
 		to 100% viewport width at responsive sizes. */
 	#wpadminbar .ab-top-menu > .menupop > .ab-sub-wrapper {
-		min-width: -webkit-fit-content;
 		min-width: -moz-fit-content;
 		min-width: fit-content;
 	}

wp-includes/css/admin-bar.css

@@ -988,7 +988,6 @@ html:lang(he-il) .rtl #wpadminbar * {
 	/* Override default min-width so dropdown lists aren't stretched
 		to 100% viewport width at responsive sizes. */
 	#wpadminbar .ab-top-menu > .menupop > .ab-sub-wrapper {
-		min-width: -webkit-fit-content;
 		min-width: -moz-fit-content;
 		min-width: fit-content;
 	}

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-alpha-51455';
+$wp_version = '5.9-alpha-51456';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.