Diagnostics: Add realtime-cpu-chart component

Skeleton component for cpu chart
https://screenshot.googleplex.com/C7PPFcPZ95FZXJ8

Bug: 1125150
Test: browser_tests --gtest_Filter=DiagnosticsApp*
Change-Id: Ic2ae0209fb71f894df8a4b3a4e61547975ff0f11
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2438882
Commit-Queue: Joon Ahn <joonbug@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812125}

chromeos/components/diagnostics_ui/resources/BUILD.gn

@@ -24,6 +24,7 @@ js_type_check("closure_compile_module") {
     ":mojo_interface_provider",
     ":overview_card",
     ":percent_bar_chart",
+    ":realtime_cpu_chart",
   ]
 }
 
@@ -112,6 +113,12 @@ js_library("percent_bar_chart") {
   ]
 }
 
+js_library("realtime_cpu_chart") {
+  deps = [
+    "//third_party/polymer/v3_0/components-chromium/polymer:polymer_bundled",
+  ]
+}
+
 html_to_js("web_components") {
   js_files = [
     "battery_status_card.js",
@@ -124,5 +131,6 @@ html_to_js("web_components") {
     "memory_card.js",
     "overview_card.js",
     "percent_bar_chart.js",
+    "realtime_cpu_chart.js",
   ]
 }

chromeos/components/diagnostics_ui/resources/diagnostics_app_resources.grd

@@ -29,6 +29,7 @@
       <include name="IDR_DIAGNOSTICS_MOJO_INTERFACE_PROVIDER_JS" file="mojo_interface_provider.js" type="BINDATA"/>
       <include name="IDR_DIAGNOSTICS_OVERVIEW_CARD_JS" file="${root_gen_dir}/chromeos/components/diagnostics_ui/resources/overview_card.js" use_base_dir="false" type="BINDATA"/>
       <include name="IDR_DIAGNOSTICS_PERCENT_BAR_CHART_JS" file="${root_gen_dir}/chromeos/components/diagnostics_ui/resources/percent_bar_chart.js" use_base_dir="false" type="BINDATA"/>
+      <include name="IDR_DIAGNOSTICS_REALTIME_CPU_CHART_JS" file="${root_gen_dir}/chromeos/components/diagnostics_ui/resources/realtime_cpu_chart.js" use_base_dir="false" type="BINDATA"/>
       <include name="IDR_DIAGNOSTICS_SHARED_CSS_JS" file="${root_gen_dir}/chromeos/components/diagnostics_ui/resources/diagnostics_shared_css.js" use_base_dir="false" type="BINDDATA"/>
       <include name="IDR_DIAGNOSTICS_TYPES_JS" file="diagnostics_types.js" type="BINDATA"/>
     </includes>

chromeos/components/diagnostics_ui/resources/realtime_cpu_chart.html

+<style include="diagnostics-shared diagnostics-fonts">
+</style>
+
+<div id="chart-wrapper">
+  <div>[[user]]</div>
+  <div>[[system]]</div>
+</div>

chromeos/components/diagnostics_ui/resources/realtime_cpu_chart.js

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import './diagnostics_fonts_css.js';
+import './diagnostics_shared_css.js';
+
+import {html, Polymer} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+
+/**
+ * @fileoverview
+ * 'realtime-cpu-chart' is a moving line graph component used to display a
+ * realtime cpu usage information.
+ */
+Polymer({
+  is: 'realtime-cpu-chart',
+
+  _template: html`{__html_template__}`,
+
+  properties: {
+    user: {
+      type: Number,
+      value: 0,
+    },
+
+    system: {
+      type: Number,
+      value: 0,
+    },
+  },
+});