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

Source/core/html/shadow/SpinButtonElement.h

Index: Source/core/html/shadow/SpinButtonElement.h
diff --git a/Source/core/html/shadow/SpinButtonElement.h b/Source/core/html/shadow/SpinButtonElement.h
index 03f7da403c21f535de89f9d6b32c6abb057799d9..77d031e2ac9495cda3b569f857499b1c819b3c34 100644
--- a/Source/core/html/shadow/SpinButtonElement.h
+++ b/Source/core/html/shadow/SpinButtonElement.h
@@ -21,9 +21,9 @@
  * 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.
  */
- 
+
 #ifndef SpinButtonElement_h
 #define SpinButtonElement_h
 
@@ -60,7 +60,7 @@ public:
     void removeSpinButtonOwner() { m_spinButtonOwner = 0; }
 
     void step(int amount);
-    
+
     virtual bool willRespondToMouseMoveEvents() OVERRIDE;
     virtual bool willRespondToMouseClickEvents() OVERRIDE;