Attribute Quick Access perfect match to its actual provider

The perfect-match removal loop in computeMatchingEntries never ran. Its
body was guarded by "if (perfectMatchProvider != null)" while that
variable starts null and is only assigned inside the guard, making the
assignment unreachable. The predicate also tested prevPickIds instead of
the perfect match, a leftover copy of the previous-picks removal above.

Consequently perfectMatchProvider stayed null, so the pinned perfect
match was always attributed to providers[0], and the perfect match was
never removed from its provider list (it could appear twice in the
show-all-matches view).

Find the provider whose elements contain the perfect match, remove it by
identity, and record that provider.

Author: vogella

bundles/org.eclipse.ui.workbench/eclipseui/org/eclipse/ui/internal/quickaccess/QuickAccessContents.java

@@ -519,12 +519,11 @@ private List<QuickAccessEntry>[] computeMatchingEntries(String filter, QuickAcce
 		QuickAccessProvider perfectMatchProvider = null;
 		if (perfectMatch != null) {
 			for (Entry<QuickAccessProvider, List<QuickAccessElement>> entry : elementsForProviders.entrySet()) {
-				if (perfectMatchProvider != null) {
-					List<QuickAccessElement> filteredElements = new ArrayList<>(entry.getValue());
-					if (filteredElements.removeIf(element -> prevPickIds.contains(element.getId()))) {
-						entry.setValue(filteredElements);
-						perfectMatchProvider = entry.getKey();
-					}
+				List<QuickAccessElement> filteredElements = new ArrayList<>(entry.getValue());
+				if (filteredElements.removeIf(element -> element == perfectMatch)) {
+					entry.setValue(filteredElements);
+					perfectMatchProvider = entry.getKey();
+					break;
 				}
 			}
 		}