Fix Ctrl+F7 view switcher showing same name for multi-instance views

Remove the getPartName() override in ViewReference that always returned
the static descriptor label from plugin.xml. The parent class
WorkbenchPartReference.getPartName() returns part.getLocalizedLabel()
which reflects the dynamic name set by views via setPartName().

This is a generic fix for all multi-instance views (Terminal, Console,
Search) that customize their part name.

Fixes eclipse-platform/eclipse.platform#2774

Author: Philipp0205

bundles/org.eclipse.ui.workbench/eclipseui/org/eclipse/ui/internal/ViewReference.java

@@ -68,11 +68,6 @@ public void persist() {
 		}
 	}
 
-	@Override
-	public String getPartName() {
-		return descriptor == null ? "" : descriptor.getLabel(); //$NON-NLS-1$
-	}
-
 	@Override
 	public String getSecondaryId() {
 		MPart part = getModel();