Send screenshots back to the client for debugging

chrome/test/webdriver/session.cc

Index: chrome/test/webdriver/session.cc
diff --git a/chrome/test/webdriver/session.cc b/chrome/test/webdriver/session.cc
index 400c7eb42915ce74bb5d74ceabe435380e71bfb0..5d6ba6dd4ffceebd3ff6a229eb2e69b359d59917 100644
--- a/chrome/test/webdriver/session.cc
+++ b/chrome/test/webdriver/session.cc
@@ -7,6 +7,7 @@
 #include <sstream>
 #include <vector>
 
+#include "base/base64.h"
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
@@ -17,6 +18,7 @@
 #include "base/process.h"
 #include "base/process_util.h"
 #include "base/scoped_ptr.h"
+#include "base/scoped_temp_dir.h"
 #include "base/stringprintf.h"
 #include "base/string_number_conversions.h"
 #include "base/string_split.h"
@@ -65,8 +67,10 @@ bool Session::Init(const FilePath& browser_dir) {
   } else {
     LOG(ERROR) << "Cannot start session thread";
   }
+
   if (!success)
     delete this;
+
   return success;
 }
 
@@ -355,6 +359,56 @@ bool Session::GetWindowIds(std::vector<int>* window_ids) {
   return success;
 }
 
+bool Session::CaptureEntirePageAsPNG(const FilePath& path) {
+  bool success = false;
+  RunSessionTask(NewRunnableMethod(
+      automation_.get(),
+      &Automation::CaptureEntirePageAsPNG,
+      current_window_id_,
+      path,
+      &success));
+  return success;
+}
+
+bool Session::ScreenshotAsBase64(std::string* screenshot) {
+  ScopedTempDir screenshots_dir;
+
+  // Create a temp directory for screenshots.
+  if (!screenshots_dir.CreateUniqueTempDir()) {
+    LOG(ERROR) << "Could not make a temp directory for screenshots";
+    return false;
+  }
+
+  // Generate a temp file name for the screenshot
+  std::string file = screenshots_dir.path().value() + "screen";
+
+#ifdef OS_POSIX
+  FilePath path = FilePath(file.c_str());
+#elif OS_WIN
+  FilePath path = FilePath(ASCIIToWide(file.s_ctr()));
+#endif
+
+  // Capture the current tab as a PNG file.
+  if (!CaptureEntirePageAsPNG(path)) {
+    LOG(ERROR) << "Capturing tab page as PNG failed";
+    return false;
+  }
+
+  std::string raw_bytes;
+  if (!file_util::ReadFileToString(path, &raw_bytes)) {
+    LOG(ERROR) << "Opening PNG file failed";
+    return false;
+  }
+
+  // Make a base64 encoded string for the raw PNG data
+  if (!base::Base64Encode(raw_bytes, screenshot)) {
+    LOG(ERROR) << "Encoding the PNG to base64 format failed";
+    return false;
+  }
+
+  return true;
+}
+
 ErrorCode Session::SwitchToWindow(const std::string& name) {
   int switch_to_id = 0;
   int name_no = 0;
@@ -560,6 +614,38 @@ bool Session::WaitForAllTabsToStopLoading() {
   return success;
 }
 
+std::string Session::Id() const {
+  return id_;
+}
+
+int Session::ImplicitWait() const {
+  return implicit_wait_;
+}
+
+void Session::SetImplicitWait(const int& timeout) {
+  implicit_wait_ = timeout > 0 ? timeout : 0;
+}
+
+Session::InputSpeed Session::Speed() const {
+  return speed_;
+}
+
+void Session::SetSpeed(const InputSpeed& speed) {
+  speed_ = speed;
+}
+
+std::string Session::CurrentFrameXPath() const {
+  return current_frame_xpath_;
+}
+
+void Session::SetCurrentFrameXPath(const std::string& xpath) {
+  current_frame_xpath_ = xpath;
+}
+
+int Session::CurrentWindowId() const {
+  return current_window_id_;
+}
+
 void Session::RunSessionTask(Task* task) {
   base::WaitableEvent done_event(false, false);
   thread_.message_loop_proxy()->PostTask(FROM_HERE, NewRunnableMethod(