Bug 31395 Child window of Preferences dialog centers between screens
On the Preferences->Java->Code Generation->Names tab, the Edit button opens a dialog that is split between multiple monitors, instead of centering on the main Preference window like the rest of its child windows do.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/CompilerConfigurationBlock.java
Composite styleComposite= new Composite(folder, SWT.NULL);
		styleComposite.setLayout(layout);
		Label description= new Label(styleComposite, SWT.WRAP);
		description.setText(PreferencesMessages.getString("CompilerConfigurationBlock.style.description")); 
		GridData gd= new GridData();
		gd.horizontalSpan= 2;
		gd.widthHint= fPixelConverter.convertWidthInCharsToPixels(50);
		description.setLayoutData(gd);
		String label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_overriding_pkg_dflt.label"); 
		addComboBox(styleComposite, label, PREF_PB_OVERRIDING_PACKAGE_DEFAULT_METHOD, errorWarningIgnore, errorWarningIgnoreLabels, 0);			
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_method_naming.label"); 
		addComboBox(styleComposite, label, PREF_PB_METHOD_WITH_CONSTRUCTOR_NAME, errorWarningIgnore, errorWarningIgnoreLabels, 0);			
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_incompatible_interface_method.label"); 
		addComboBox(styleComposite, label, PREF_PB_INCOMPATIBLE_INTERFACE_METHOD, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_hidden_catchblock.label"); 
		addComboBox(styleComposite, label, PREF_PB_HIDDEN_CATCH_BLOCK, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_static_access_receiver.label"); 
		addComboBox(styleComposite, label, PREF_PB_STATIC_ACCESS_RECEIVER, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_synth_access_emul.label"); 
		addComboBox(styleComposite, label, PREF_PB_SYNTHETIC_ACCESS_EMULATION, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_no_effect_assignment.label"); 
		addComboBox(styleComposite, label, PREF_PB_NO_EFFECT_ASSIGNMENT, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		label= PreferencesMessages.getString("CompilerConfigurationBlock.pb_char_array_in_concat.label"); 
		addComboBox(styleComposite, label, PREF_PB_CHAR_ARRAY_IN_CONCAT, errorWarningIgnore, errorWarningIgnoreLabels, 0);
		return styleComposite;
	}
	private Composite createOthersTabContent(TabFolder folder) {