[376] Remove code now accessible as APIs in GEF

This commit removes the code duplicated from GEF as it is now available
as API in GEF (through issue
eclipse-gef/gef-classic#426).

Bug: #376

plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/tools/internal/ui/SnapToAllDragEditPartsTracker.java

@@ -12,8 +12,6 @@
  *******************************************************************************/
 package org.eclipse.sirius.diagram.ui.tools.internal.ui;
 
-import java.util.Date;
-
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.draw2d.FigureCanvas;
 import org.eclipse.draw2d.PositionConstants;
@@ -190,24 +188,24 @@ protected boolean handleKeyDown(KeyEvent event) {
 
             // Reproduce the "acceleration behavior" of
             // org.eclipse.gef.tools.DragEditPartsTracker.handleKeyDown(KeyEvent) to get the increment to use.
-            siriusAccStepIncrement();
+            accStepIncrement();
             PrecisionPoint moveDelta;
             switch (event.keyCode) {
             case SWT.ARROW_DOWN:
-                moveDelta = new PrecisionPoint(0, siriusAccGetStep());
+                moveDelta = new PrecisionPoint(0, accGetStep());
                 break;
             case SWT.ARROW_UP:
-                moveDelta = new PrecisionPoint(0, -siriusAccGetStep());
+                moveDelta = new PrecisionPoint(0, -accGetStep());
                 break;
             case SWT.ARROW_RIGHT:
-                int stepping = siriusAccGetStep();
+                int stepping = accGetStep();
                 if (isCurrentViewerMirrored2()) {
                     stepping = -stepping;
                 }
                 moveDelta = new PrecisionPoint(stepping, 0);
                 break;
             case SWT.ARROW_LEFT:
-                int step = -siriusAccGetStep();
+                int step = -accGetStep();
                 if (isCurrentViewerMirrored2()) {
                     step = -step;
                 }
@@ -260,7 +258,7 @@ protected boolean handleKeyUp(KeyEvent event) {
         }
         if (acceptArrowKey(event)) {
             moveWithArrowKeysSiriusMode = false;
-            siriusAccStepReset();
+            accStepReset();
         }
         return super.handleKeyUp(event);
     }
@@ -349,52 +347,4 @@ protected boolean updateTargetUnderMouse() {
         }
         return super.updateTargetUnderMouse();
     }
-
-    /**
-     * Method overridden to initialize the cloned field {@link #accessibleBegin}. No longer necessary as soon as GEF
-     * issue https://github.com/eclipse/gef-classic/issues/426 will be done.
-     * 
-     * @see org.eclipse.gef.tools.AbstractTool#activate()
-     */
-    @Override
-    public void activate() {
-        super.activate();
-        siriusAccStepReset();
-    }
-
-    /**
-     * Method cloned from {@link org.eclipse.gef.tools.AbstractTool#.accGetStep()} to have the same behavior here. No
-     * longer necessary as soon as GEF issue https://github.com/eclipse/gef-classic/issues/426 will be done.
-     * 
-     * @return the current computed step.
-     */
-    int siriusAccGetStep() {
-        return accessibleStep;
-    }
-
-    /**
-     * Method cloned from {@link org.eclipse.gef.tools.AbstractTool#accStepIncrement()} to have the same behavior here.
-     * No longer necessary as soon as GEF issue https://github.com/eclipse/gef-classic/issues/426 will be done.
-     * 
-     * @return the current computed step.
-     */
-    void siriusAccStepIncrement() {
-        if (accessibleBegin == -1) {
-            accessibleBegin = new Date().getTime();
-            accessibleStep = 1;
-        } else {
-            accessibleStep = 4;
-            long elapsed = new Date().getTime() - accessibleBegin;
-            if (elapsed > 1000)
-                accessibleStep = Math.min(16, (int) (elapsed / 150));
-        }
-    }
-
-    /**
-     * Method cloned from {@link org.eclipse.gef.tools.AbstractTool#accStepReset()} to have the same behavior here. No
-     * longer necessary as soon as GEF issue https://github.com/eclipse/gef-classic/issues/426 will be done.
-     */
-    void siriusAccStepReset() {
-        accessibleBegin = -1;
-    }
 }