Revert workaround for popper glitch, fix regression

Revert the workaround that existed to dodge popper.js glitch where the
popover appeared in the wrong position first and a few milliseconds
later in the right place.

This fixes a regression where the regular Popover wasn't working any
more.

Signed-off-by: Vincent Petry <vincent@nextcloud.com>

src/components/Popover/Popover.vue

@@ -52,7 +52,7 @@ With a `<button>` as a trigger:
 <template>
 	<VPopover
 		v-bind="$attrs"
-		:popover-base-class="doShowMenu ? 'popover' : 'popover popover__hidden'"
+		popover-base-class="popover"
 		popover-wrapper-class="popover__wrapper"
 		popover-arrow-class="popover__arrow"
 		popover-inner-class="popover__inner"
@@ -74,34 +74,6 @@ export default {
 	components: {
 		VPopover,
 	},
-	props: {
-		open: {
-			type: Boolean,
-			default: false,
-		},
-	},
-	data() {
-		return {
-			doShowMenu: false,
-		}
-	},
-
-	watch: {
-		open(newValue) {
-			if (newValue === true) {
-				// show with delay to allow position calculation to happen for dynamic contents,
-				// otherwise the popover will appear in the wrong place first and be visible,
-				// and then in the next tick it repositions itself
-				// Note: we can't use this.$nextTick here as it happens too early before
-				// v-tooltip's position calculation happens
-				window.setTimeout(() => {
-					this.doShowMenu = newValue
-				}, 2)
-			} else {
-				this.doShowMenu = false
-			}
-		},
-	},
 }
 </script>
 
@@ -114,15 +86,6 @@ $arrow-width: 10px;
 
 	filter: drop-shadow(0 1px 10px var(--color-box-shadow));
 
-	&__hidden {
-		/* same as visibility-hidden but keep the size to avoid resizes on show */
-		/* !important is here to override inline styles set by v-tooltip for initial show */
-		visibility: hidden !important;
-		left: -10000px !important;
-		top: auto !important;
-		transform: transform3d(-10000, -10000, 0) !important;
-	}
-
 	&__inner {
 		padding: 0;
 		color: var(--color-main-text);