Fix input injector on Linux to release all keys before injecting text event.

remoting/host/input_injector_x11.cc

Index: remoting/host/input_injector_x11.cc
diff --git a/remoting/host/input_injector_x11.cc b/remoting/host/input_injector_x11.cc
index 1852e9fabc50ab43f2b8ca516d3e752f3674eb7c..55690da30319b8511e4c5b33fe732d50e8e43db4 100644
--- a/remoting/host/input_injector_x11.cc
+++ b/remoting/host/input_injector_x11.cc
@@ -327,6 +327,14 @@ void InputInjectorX11::Core::InjectTextEvent(const TextEvent& event) {
     return;
   }
 
+  // Release all keys before injecting text event. This is necessary to avoid
+  // any interference with the currently pressed keys. E.g. if Shift is pressed
+  // when TextEvent is received.
+  for (int key : pressed_keys_) {
+    XTestFakeKeyEvent(display_, key, False, CurrentTime);
+  }
+  pressed_keys_.clear();
+
   const std::string text = event.text();
   for (int32 index = 0; index < static_cast<int32>(text.size()); ++index) {
     uint32_t code_point;