feat(dialog): support minWidth, minHeight, maxWidth and maxHeight

* Adds Dialog support for `minWidth`, `minHeight`, `maxWidth` and `maxHeight` via config. Mostly delegates to Overlay.
* Moves declared `max-width` on `. mat-dialog-container` stylesheet to be authored via `MatDialogConfig`, providing the same default `80vw` value. Without this change, there would likely be undesired layout results due to different constraints being set on the overlay container vs the nested the dialog container.
* Added note on `minHeight` and `maxHeight` regarding the potential need to also set a `height` due to the rules around computed height resolution (https://www.w3.org/TR/CSS2/visudet.html#min-max-widths).  Any value set on `height` as a default would probably be assuming too much and may have varying results across browsers.

Author: emilio-martinez

src/lib/dialog/dialog-config.ts

@@ -57,6 +57,26 @@ export class MatDialogConfig {
   /** Height of the dialog. */
   height?: string = '';
 
+  /** Min-width of the dialog. */
+  minWidth?: string = '';
+
+  /**
+   * Min-height of the dialog.
+   * For this value to be effectively applied, `height` may also need to be defined.
+   * See https://www.w3.org/TR/CSS2/visudet.html#min-max-widths
+   */
+  minHeight?: string = '';
+
+  /** Max-width of the dialog. */
+  maxWidth?: string = '80vw';
+
+  /**
+   * Max-height of the dialog.
+   * For this value to be effectively applied, `height` may also need to be defined.
+   * See https://www.w3.org/TR/CSS2/visudet.html#min-max-widths
+   */
+  maxHeight?: string = '';
+
   /** Position overrides. */
   position?: DialogPosition;
 

src/lib/dialog/dialog.scss

@@ -5,7 +5,6 @@
 
 $mat-dialog-padding: 24px !default;
 $mat-dialog-border-radius: 2px !default;
-$mat-dialog-max-width: 80vw !default;
 $mat-dialog-max-height: 65vh !default;
 $mat-dialog-button-margin: 8px !default;
 
@@ -17,7 +16,6 @@ $mat-dialog-button-margin: 8px !default;
   border-radius: $mat-dialog-border-radius;
   box-sizing: border-box;
   overflow: auto;
-  max-width: $mat-dialog-max-width;
   outline: 0;
 
   // The dialog container should completely fill its parent overlay element.

src/lib/dialog/dialog.ts

@@ -190,7 +190,11 @@ export class MatDialog {
       scrollStrategy: this._scrollStrategy(),
       panelClass: dialogConfig.panelClass,
       hasBackdrop: dialogConfig.hasBackdrop,
-      direction: dialogConfig.direction
+      direction: dialogConfig.direction,
+      minWidth: dialogConfig.minWidth,
+      minHeight: dialogConfig.minHeight,
+      maxWidth: dialogConfig.maxWidth,
+      maxHeight: dialogConfig.maxHeight
     });
 
     if (dialogConfig.backdropClass) {