Fix trailing whitespace in .cpp, .h, and .idl files

Source/core/dom/CompositionEvent.h

Index: Source/core/dom/CompositionEvent.h
diff --git a/Source/core/dom/CompositionEvent.h b/Source/core/dom/CompositionEvent.h
index 167b6d1945595436b1c50739c1a19b18ce6f313b..cf39f9b188c272aba3c6b943ba2e66a038cc7538 100644
--- a/Source/core/dom/CompositionEvent.h
+++ b/Source/core/dom/CompositionEvent.h
@@ -9,7 +9,7 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
@@ -20,7 +20,7 @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  */