fix: offset changes not being deteched in md-select

Author: crisbeto

src/lib/core/overlay/overlay-directives.ts

@@ -146,15 +146,15 @@ export class ConnectedOverlayDirective implements OnDestroy, OnChanges {
 
   ngOnChanges(changes: SimpleChanges) {
     if (changes['open']) {
-      changes['open'].currentValue ? this._attachOverlay() : this._detachOverlay();
+      this.open ? this._attachOverlay() : this._detachOverlay();
     }
 
     if (changes['offsetX'] && this._position) {
-      this._position.withOffsetX(changes['offsetX'].currentValue);
+      this._position.withOffsetX(this.offsetX);
     }
 
     if (changes['offsetY'] && this._position) {
-      this._position.withOffsetY(changes['offsetY'].currentValue);
+      this._position.withOffsetY(this.offsetY);
     }
   }
 

src/lib/select/select.ts

@@ -577,6 +577,7 @@ export class MdSelect implements AfterContentInit, ControlValueAccessor, OnDestr
     }
 
     this._checkOverlayWithinViewport(maxScroll);
+    this._changeDetectorRef.detectChanges();
   }
 
   /**