DevTools: make debugger's rawLocationToUILocation return nullable type

third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js

Index: third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js b/third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js
index a7fc4e4212e97ce072d47c819b8933dddb1184b7..78168992f020d48b0446b380201b39ac6f4cfd31 100644
--- a/third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js
+++ b/third_party/WebKit/Source/devtools/front_end/sources/SourcesPanel.js
@@ -1159,8 +1159,10 @@ Sources.SourcesPanel.DebuggerLocationRevealer = class {
   reveal(rawLocation, omitFocus) {
     if (!(rawLocation instanceof SDK.DebuggerModel.Location))
       return Promise.reject(new Error('Internal error: not a debugger location'));
-    Sources.SourcesPanel.instance().showUILocation(
-        Bindings.debuggerWorkspaceBinding.rawLocationToUILocation(rawLocation), omitFocus);
+    var uiLocation = Bindings.debuggerWorkspaceBinding.rawLocationToUILocation(rawLocation);
+    if (!uiLocation)
+      return Promise.resolve();
+    Sources.SourcesPanel.instance().showUILocation(uiLocation, omitFocus);
     return Promise.resolve();
   }
 };