Delayload bluetooth imports on Windows.

device/bluetooth/bluetooth_adapter_win.cc

Index: device/bluetooth/bluetooth_adapter_win.cc
diff --git a/device/bluetooth/bluetooth_adapter_win.cc b/device/bluetooth/bluetooth_adapter_win.cc
index 5924cd9a433ae428154de364d46c10b43093bb5a..26a9fc5ae01d8ac3122d23b78662076c218d9f12 100644
--- a/device/bluetooth/bluetooth_adapter_win.cc
+++ b/device/bluetooth/bluetooth_adapter_win.cc
@@ -7,20 +7,58 @@
 #include "device/bluetooth/bluetooth_adapter_win.h"
 
 #include <BluetoothAPIs.h>
+#if defined(_WIN32_WINNT_WIN8)
+// The Windows 8 SDK defines FACILITY_VISUALCPP in winerror.h.
+#undef FACILITY_VISUALCPP
+#endif
+#include <delayimp.h>
 #include <string>
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/stringprintf.h"
 #include "base/sys_string_conversions.h"
+#include "base/threading/thread_restrictions.h"
 
-# pragma comment(lib, "Bthprops.lib")
+#pragma comment(lib, "Bthprops.lib")
+#pragma comment(lib, "delayimp.lib")
 
 namespace {
 
 const BLUETOOTH_FIND_RADIO_PARAMS bluetooth_adapter_param =
     { sizeof(BLUETOOTH_FIND_RADIO_PARAMS) };
 
+// A frame-based exception handler filter function for a handler for exceptions
+// generated by the Visual C++ delay loader helper function.
+int FilterVisualCPPExceptions(DWORD exception_code) {
+  return HRESULT_FACILITY(exception_code) == FACILITY_VISUALCPP ?
+      EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH;
+}
+
+// Returns true if the machine has a bluetooth stack available. The first call
+// to this function will involve file IO, so it should be done on an
+// appropriate thread. This function is not threadsafe.
+bool HasBluetoothStack() {
+  static enum {
+    HBS_UNKNOWN,
+    HBS_YES,
+    HBS_NO,
+  } has_bluetooth_stack = HBS_UNKNOWN;
+
+  if (has_bluetooth_stack == HBS_UNKNOWN) {
+    base::ThreadRestrictions::AssertIOAllowed();
+    HRESULT hr = E_FAIL;
+    __try {
+      hr = __HrLoadAllImportsForDll("bthprops.cpl");
+    } __except(FilterVisualCPPExceptions(::GetExceptionCode())) {
+      hr = E_FAIL;
+    }
+    has_bluetooth_stack = SUCCEEDED(hr) ? HBS_YES : HBS_NO;
+  }
+
+  return has_bluetooth_stack == HBS_YES;
+}
+
 }  // namespace
 
 namespace device {
@@ -94,6 +132,11 @@ void BluetoothAdapterWin::ReadLocalOutOfBandPairingData(
 }
 
 void BluetoothAdapterWin::UpdateAdapterState() {
+  // TODO(youngki): Move this check to the earliest point reasonable so that no
+  // attempts are made to do any bluetooth processing if no BT stack is present.
+  if (!HasBluetoothStack())
+    return;
+
   HBLUETOOTH_RADIO_FIND bluetooth_adapter_handle = NULL;
   BLUETOOTH_RADIO_INFO bluetooth_adapter_info =
       { sizeof(BLUETOOTH_RADIO_INFO), 0 };