network-health: add signal strength to network health snapshot

This change adds a new field to the network snapshot, signal strength.
It is populated with the signal strength of wireless network devices as
measured from the device. The value ranges from 0 - 100. This value is
also added to the network health summary UI and feedback reports.

Bug: chromium:1128460
Test: checked chrome://network for signal strength
Change-Id: I447d5753b16ca79d9383543bb16a669eb7b80184
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2412216
Commit-Queue: Trent Begin <tbegin@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809997}

chrome/browser/chromeos/net/network_health/network_health.cc

@@ -9,6 +9,7 @@
 
 #include "chromeos/network/network_event_log.h"
 #include "chromeos/services/network_config/in_process_instance.h"
+#include "chromeos/services/network_config/public/cpp/cros_network_config_util.h"
 #include "chromeos/services/network_config/public/mojom/cros_network_config.mojom.h"
 #include "chromeos/services/network_health/public/mojom/network_health.mojom.h"
 
@@ -69,6 +70,11 @@ mojom::NetworkPtr CreateNetwork(
     net->state = ConnectionStateToNetworkState(net_prop->connection_state);
     net->name = net_prop->name;
     net->guid = net_prop->guid;
+    if (chromeos::network_config::NetworkTypeMatchesType(
+            net_prop->type, network_config::mojom::NetworkType::kWireless)) {
+      net->signal_strength = network_health::mojom::UInt32Value::New(
+          network_config::GetWirelessSignalStrength(net_prop.get()));
+    }
   } else {
     net->state = DeviceStateToNetworkState(device_prop->device_state);
   }

chrome/browser/chromeos/system_logs/network_health_source.cc

@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/bind.h"
+#include "base/strings/string_number_conversions.h"
 #include "chrome/browser/chromeos/net/network_health/network_health_service.h"
 #include "chromeos/network/network_event_log.h"
 #include "content/public/browser/browser_thread.h"
@@ -34,6 +35,11 @@ std::string GetFormattedString(
 
     output << "Type: " << net->type << "\n";
     output << "State: " << net->state << "\n";
+    output << "Signal Strength: "
+           << (net->signal_strength
+                   ? base::NumberToString(net->signal_strength->value)
+                   : "N/A")
+           << "\n";
     output << "MAC Address: " << net->mac_address.value_or("N/A") << "\n";
     output << "\n";
   }

chromeos/services/network_health/public/mojom/network_health.mojom

@@ -31,6 +31,13 @@ enum NetworkState {
   kOnline,
 };
 
+// Wrapper for optional uint32. // TODO(https://crbug.com/657632): Remove this
+// once Mojo properly supports this.
+struct UInt32Value {
+  // The value of the uint64.
+  uint32 value;
+};
+
 // Contains information for a single network connection and underlying
 // network technology e.g WiFi.
 struct Network {
@@ -42,6 +49,11 @@ struct Network {
   string? name;
   // Optional string for the network's mac_address.
   string? mac_address;
+  // Signal strength of the network provided only for wireless networks. Values
+  // are normalized between 0 to 100 inclusive. Values less than 30 are
+  // considered potentially problematic for the connection. See
+  // src/platform2/shill/doc/service-api.txt for more details.
+  UInt32Value? signal_strength;
 };
 
 // Aggregate structure for all of the network health state.

ui/webui/resources/cr_components/chromeos/network_health/network_health_summary.html

@@ -31,6 +31,7 @@
         <td>[[i18n('OncName')]]</td>
         <td>[[i18n('OncType')]]</td>
         <td>[[i18n('NetworkHealthState')]]</td>
+        <td>[[i18n('OncWiFi-SignalStrength')]]</td>
         <td>[[i18n('OncMacAddress')]]</td>
       </tr>
       <hr>
@@ -40,6 +41,7 @@
           <td>[[network.name]]</td>
           <td>[[getNetworkTypeString_(network.type)]]</td>
           <td>[[getNetworkStateString_(network.state)]]</td>
+          <td>[[getSignalStrengthString_(network.signalStrength)]]</td>
           <td>[[network.macAddress]]</td>
         </tr>
       </template>

ui/webui/resources/cr_components/chromeos/network_health/network_health_summary.js

@@ -91,4 +91,14 @@ Polymer({
   getNetworkTypeString_(type) {
     return this.i18n('OncType' + OncMojo.getNetworkTypeString(type));
   },
+
+  /**
+   * Returns a string for the given signal strength.
+   * @private
+   * @param {?chromeos.networkHealth.mojom.UInt32Value} signalStrength
+   * @return {string}
+   */
+  getSignalStrengthString_(signalStrength) {
+    return signalStrength ? signalStrength.value.toString() : '';
+  },
 });