Fix bug where CSS styles are requested after node is destroyed

ash/common/devtools/ash_devtools_css_agent.cc

Index: ash/common/devtools/ash_devtools_css_agent.cc
diff --git a/ash/common/devtools/ash_devtools_css_agent.cc b/ash/common/devtools/ash_devtools_css_agent.cc
index 295b53a3b35307921173814b2b0cca68196a8fe4..a23405c9918e4b7d693716114fae8b99dd750198 100644
--- a/ash/common/devtools/ash_devtools_css_agent.cc
+++ b/ash/common/devtools/ash_devtools_css_agent.cc
@@ -68,6 +68,9 @@ ui::devtools::protocol::Response AshDevToolsCSSAgent::getMatchedStylesForNode(
     ui::devtools::protocol::Maybe<ui::devtools::protocol::CSS::CSSStyle>*
         inlineStyle) {
   *inlineStyle = GetStylesForNode(nodeId);
+  if (!inlineStyle)
+    return ui::devtools::protocol::Response::Error(
+        "Node with that id not found");

[sadrul, 2016/11/25 18:30:32]

Add {}

[Sarmad Hashmi, 2016/11/26 01:48:20]

Done.

   return ui::devtools::protocol::Response::OK();
 }
 
@@ -85,7 +88,6 @@ AshDevToolsCSSAgent::GetStylesForNode(int nodeId) {
   if (view)
     return BuildStyles(view);
 
-  NOTREACHED();
   return nullptr;
 }