DevTools: introduce RecordEnumeratedHistogram method.

chrome/browser/devtools/devtools_ui_bindings.cc

Index: chrome/browser/devtools/devtools_ui_bindings.cc
diff --git a/chrome/browser/devtools/devtools_ui_bindings.cc b/chrome/browser/devtools/devtools_ui_bindings.cc
index 03c3c97ae391af45b3c3c767c4f90f82e9308181..78b82107432d19deb8dbb0a0b07d1bd24ea20ebf 100644
--- a/chrome/browser/devtools/devtools_ui_bindings.cc
+++ b/chrome/browser/devtools/devtools_ui_bindings.cc
@@ -749,6 +749,17 @@ void DevToolsUIBindings::RecordActionUMA(const std::string& name, int action) {
     UMA_HISTOGRAM_ENUMERATION(name, action, kDevToolsPanelShownBoundary);
 }
 
+void DevToolsUIBindings::RecordUMA(const std::string& name,
+                                   int action,
+                                   int bucket_size) {
+  CHECK(0 < bucket_size && bucket_size < 100);

[Tom Sepez, 2015/04/03 17:46:51]

CHECK-ing in the browser is bad when the renderer is at fault.  If any of the
conditions here aren't met (including an unknown name below), you want to
terminate the renderer (e.g. BadMessageReceived() if it's available in this
context). 

[lushnikov, 2015/04/06 10:10:39]

Done.

+  CHECK(0 <= action && action < bucket_size);
+
+  if (name == kDevToolsActionTakenHistogram ||
+      name == kDevToolsPanelShownHistogram)
+    UMA_HISTOGRAM_ENUMERATION(name, action, bucket_size);
+}
+
 void DevToolsUIBindings::SendJsonRequest(const DispatchCallback& callback,
                                          const std::string& browser_id,
                                          const std::string& url) {