Send screenshots back to the client for debugging

chrome/test/webdriver/automation.cc

Index: chrome/test/webdriver/automation.cc
diff --git a/chrome/test/webdriver/automation.cc b/chrome/test/webdriver/automation.cc
index f40d8e9afeb1b64c3b96f1c0f9866784b35ee8af..d480d58410cce1782e65a437dc73f9d98c6fcef9 100644
--- a/chrome/test/webdriver/automation.cc
+++ b/chrome/test/webdriver/automation.cc
@@ -259,6 +259,18 @@ void Automation::SendWebKeyEvent(int tab_id,
   }
 }
 
+void Automation::CaptureEntirePageAsPNG(int tab_id,
+                                        const FilePath& path,
+                                        bool* success) {
+  TabProxy* tab = GetTabById(tab_id);
+  if (!tab) {
+    *success = false;
+    return;
+  }
+
+  *success = tab->CaptureEntirePageAsPNG(path);
+}
+
 void Automation::NavigateToURL(int tab_id,
                                const std::string& url,
                                bool* success) {