docs: fix up button-types and dialog-content examples (#12320)

* Fixes the scrollable dialog content demo not scrolling properly. Also fixes up some of typography and alignment.
* Fixes the spacing and alignment on the `button-types` demo.

Author: crisbeto

src/material-examples/button-types/button-types-example.css

@@ -1,10 +1,4 @@
-.example-button-row {
-  display: flex;
-  align-items: center;
-  justify-content: space-around;
-}
-
-.example-button-row button,
-.example-button-row a {
+.button-row button,
+.button-row a {
   margin-right: 8px;
 }

src/material-examples/dialog-content/dialog-content-example-dialog.html

@@ -1,25 +1,64 @@
 <h2 mat-dialog-title>Install Angular</h2>
-<mat-dialog-content>
-  <h3>DEVELOP ACROSS ALL PLATFORMS</h3>
-  <p>Learn one way to build applications with Angular and reuse your code and abilities to build 
+<mat-dialog-content class="mat-typography">
+  <h3>Develop across all platforms</h3>
+  <p>Learn one way to build applications with Angular and reuse your code and abilities to build
     apps for any deployment target. For web, mobile web, native mobile and native desktop.</p>
-  
-  <h3>SPEED &amp; PERFORMANCE</h3>
-  <p>Achieve the maximum speed possible on the Web Platform today, and take it further, via Web 
-    Workers and server-side rendering. Angular puts you in control over scalability. Meet huge data requirements 
-    by building data models on RxJS, Immutable.js or another push-model.</p>
-  
-  <h3>INCREDIBLE TOOLING</h3>
-  <p>Build features quickly with simple, declarative templates. Extend the template language with your own 
-    components and use a wide array of existing components. Get immediate Angular-specific help and feedback 
-    with nearly every IDE and editor. All this comes together so you can focus on building amazing apps rather 
-    than trying to make the code work.</p>
-  
-  <h3>LOVED BY MILLIONS</h3>
-  <p>From prototype through global deployment, Angular delivers the productivity and scalable infrastructure 
-    that supports Google's largest applications.</p>
+
+  <h3>Speed &amp; Performance</h3>
+  <p>Achieve the maximum speed possible on the Web Platform today, and take it further, via Web
+    Workers and server-side rendering. Angular puts you in control over scalability. Meet huge
+    data requirements by building data models on RxJS, Immutable.js or another push-model.</p>
+
+  <h3>Incredible tooling</h3>
+  <p>Build features quickly with simple, declarative templates. Extend the template language with
+    your own components and use a wide array of existing components. Get immediate Angular-specific
+    help and feedback with nearly every IDE and editor. All this comes together so you can focus
+    on building amazing apps rather than trying to make the code work.</p>
+
+  <h3>Loved by millions</h3>
+  <p>From prototype through global deployment, Angular delivers the productivity and scalable
+    infrastructure that supports Google's largest applications.</p>
+
+  <h3>What is Angular?</h3>
+
+  <p>Angular is a platform that makes it easy to build applications with the web. Angular
+    combines declarative templates, dependency injection, end to end tooling, and integrated
+    best practices to solve development challenges. Angular empowers developers to build
+    applications that live on the web, mobile, or the desktop</p>
+
+  <h3>Architecture overview</h3>
+
+  <p>Angular is a platform and framework for building client applications in HTML and TypeScript.
+  Angular is itself written in TypeScript. It implements core and optional functionality as a
+  set of TypeScript libraries that you import into your apps.</p>
+
+  <p>The basic building blocks of an Angular application are NgModules, which provide a compilation
+  context for components. NgModules collect related code into functional sets; an Angular app is
+  defined by a set of NgModules. An app always has at least a root module that enables
+  bootstrapping, and typically has many more feature modules.</p>
+
+  <p>Components define views, which are sets of screen elements that Angular can choose among and
+  modify according to your program logic and data. Every app has at least a root component.</p>
+
+  <p>Components use services, which provide specific functionality not directly related to views.
+  Service providers can be injected into components as dependencies, making your code modular,
+  reusable, and efficient.</p>
+
+  <p>Both components and services are simply classes, with decorators that mark their type and
+  provide metadata that tells Angular how to use them.</p>
+
+  <p>The metadata for a component class associates it with a template that defines a view. A
+  template combines ordinary HTML with Angular directives and binding markup that allow Angular
+  to modify the HTML before rendering it for display.</p>
+
+  <p>The metadata for a service class provides the information Angular needs to make it available
+  to components through Dependency Injection (DI).</p>
+
+  <p>An app's components typically define many views, arranged hierarchically. Angular provides
+  the Router service to help you define navigation paths among views. The router provides
+  sophisticated in-browser navigational capabilities.</p>
 </mat-dialog-content>
-<mat-dialog-actions>
+<mat-dialog-actions align="end">
   <button mat-button mat-dialog-close>Cancel</button>
   <button mat-button [mat-dialog-close]="true" cdkFocusInitial>Install</button>
 </mat-dialog-actions>

src/material-examples/dialog-content/dialog-content-example.ts

@@ -13,9 +13,7 @@ export class DialogContentExample {
   constructor(public dialog: MatDialog) {}
 
   openDialog() {
-    const dialogRef = this.dialog.open(DialogContentExampleDialog, {
-      height: '350px'
-    });
+    const dialogRef = this.dialog.open(DialogContentExampleDialog);
 
     dialogRef.afterClosed().subscribe(result => {
       console.log(`Dialog result: ${result}`);