Prepare for WebRTC network_priority becoming an enum.

This change allows network_priority to change from a double to an enum
in WebRTC without breaking chromium.

After the WebRTC change is made, this will be cleaned up using helper
functions and a switch statement.

Bug: webrtc:5658
Change-Id: I0c0f7da85d94fd7969df4f1cf184b76a05174e7f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2078849Reviewed-by: Henrik Boström <hbos@chromium.org>
Commit-Queue: Taylor <deadbeef@chromium.org>
Cr-Commit-Position: refs/heads/master@{#746612}

third_party/blink/renderer/modules/peerconnection/rtc_rtp_sender.cc

@@ -271,8 +271,19 @@ webrtc::RtpEncodingParameters ToRtpEncodingParameters(
   }
   webrtc_encoding.active = encoding->active();
   webrtc_encoding.bitrate_priority = PriorityToDouble(encoding->priority());
-  webrtc_encoding.network_priority =
-      PriorityToDouble(encoding->networkPriority());
+  // TODO(deadbeef): Make helper function once network_priority changes from a
+  // double to an enum.
+  if (encoding->networkPriority() == "very-low") {
+    webrtc_encoding.network_priority = webrtc::Priority::kVeryLow;
+  } else if (encoding->networkPriority() == "low") {
+    webrtc_encoding.network_priority = webrtc::Priority::kLow;
+  } else if (encoding->networkPriority() == "medium") {
+    webrtc_encoding.network_priority = webrtc::Priority::kMedium;
+  } else if (encoding->networkPriority() == "high") {
+    webrtc_encoding.network_priority = webrtc::Priority::kHigh;
+  } else {
+    NOTREACHED();
+  }
   if (encoding->hasMaxBitrate()) {
     webrtc_encoding.max_bitrate_bps = clampTo<int>(encoding->maxBitrate());
   }
@@ -408,8 +419,21 @@ RTCRtpSendParameters* RTCRtpSender::getParameters() {
     }
     encoding->setPriority(
         PriorityFromDouble(webrtc_encoding.bitrate_priority).c_str());
-    encoding->setNetworkPriority(
-        PriorityFromDouble(webrtc_encoding.network_priority).c_str());
+    // TODO(deadbeef): Make helper function and use switch statement once
+    // network_priority changes from a double to an enum.
+    std::string network_priority;
+    if (webrtc_encoding.network_priority == webrtc::Priority::kVeryLow) {
+      network_priority = "very-low";
+    } else if (webrtc_encoding.network_priority == webrtc::Priority::kLow) {
+      network_priority = "low";
+    } else if (webrtc_encoding.network_priority == webrtc::Priority::kMedium) {
+      network_priority = "medium";
+    } else if (webrtc_encoding.network_priority == webrtc::Priority::kHigh) {
+      network_priority = "high";
+    } else {
+      NOTREACHED();
+    }
+    encoding->setNetworkPriority(network_priority.c_str());
     if (webrtc_encoding.num_temporal_layers) {
       if (*webrtc_encoding.num_temporal_layers == 2) {
         encoding->setScalabilityMode("L1T2");