Bug 52857 [spell checking] spell checking does not work for reused editors
3.0 M7 0. enable spell checking 1. set the editor preference to close editors automatically (allow only 1 editor) 2. open a CU with misspelled words in the Java editor ==> observe: spell check warnings appear 3. open another CU with misspelled words in the Java editor ==> observe: no spell check warnings
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/spelling/SpellReconcileStrategy.java
public final boolean isError() {
			return false;
		}
		/**
		 * Does the problem word start a new sentence?
		 * 
		 * @return <code>true</code> iff it starts a new sentence, <code>false</code>
		 *               otherwise
		 */
		public final boolean isSentenceStart() {
			return fSentence;
		}
		/*
		 * @see org.eclipse.jdt.core.compiler.IProblem#isWarning()
		 */
		public final boolean isWarning() {
			return true;
		}
		/**
		 * Sets whether the problem word was found in the dictionary.
		 * 
		 * @param match
		 *                   <code>true</code> iff the word was found, <code>false</code>
		 *                   otherwise
		 */
		public final void setDictionaryMatch(final boolean match) {
			fMatch= match;
		}
		/**
		 * Sets whether the problem word starts a new sentence.