Bug 139986 [CommonNavigator] Convert catch(Error/Throwable) to SafeRunner
In several places the CN framework uses catch(Error/Throwable) to ensure that code does not bring the framework down. Change these to use SafeRunner.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/actions/CommonActionProviderDescriptor.java
public String getAppearsBeforeId() {
		return appearsBeforeId;
	}
	
	/**
	 * Only nested Action Providers have priority (as of 3.2.1). 
	 * 
	 * @return The priority associated with this Action Provider Descriptor. 
	 */
	public Priority getPriority() {
		return priority;
	}
	public int hashCode() {
		final int PRIME = 31;
		int result = 1;
		result = PRIME * result + ((definedId == null) ? 0 : definedId.hashCode());
		result = PRIME * result + ((visibilityId == null) ? 0 : visibilityId.hashCode());
		return result;
	}
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (!super.equals(obj))
			return false;
		if (getClass() != obj.getClass())
			return false;
		final CommonActionProviderDescriptor other = (CommonActionProviderDescriptor) obj;
		if (definedId == null) {
			if (other.definedId != null)
				return false;