Bug 249915 [Dialogs] TitleAreaDialog does not short circuit if message is null
M20080911-1700 When profiling use of a custom WizardDialog on Linux/GTK, a lot of time was spent in WizardPage.setMessage(...). It turns out that this was because we were setting a message of null after each keypress, and the page's description (DialogPage.getDescription()) was also null. In this case the short-circuit in TitleAreaDialog.setMessage(String, int) fails to notice that the message has not changed, and does a layout every time. For our dialog this takes about 40ms each time, which is noticeable when compounded with other work.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/TitleAreaDialog.java
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 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Konstantin Scheglov <scheglov_ke@nlmk.ru > - Fix for bug 41172
 *     [Dialogs] Bug with Image in TitleAreaDialog
 *     Sebastian Davids <sdavids@gmx.de> - Fix for bug 82064