[chromoting] Fix sticky c key with cmd on mac using usb keycode

Switch to use USB keycode for the fix for sticky keys on Mac.

BUG=101937
TEST=Build on Mac and run chromoting and press cmd+c

Review URL: https://chromiumcodereview.appspot.com/10387226

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@138205 0039d316-1c4b-4281-b951-d872f2087c98

remoting/client/plugin/mac_key_event_processor.cc

@@ -6,17 +6,21 @@
 
 #include <vector>
 
+#include "base/logging.h"
+
 namespace remoting {
 
 namespace {
 
-// A list of known keycodes.
-const int kShift = 16;
-const int kControl = 17;
-const int kOption = 18;
-const int kCapsLock = 20;
-const int kLeftCmd = 91;
-const int kRightCmd = 93;
+const unsigned int kUsbLeftControl  = 0x0700e0;
+const unsigned int kUsbLeftShift    = 0x0700e1;
+const unsigned int kUsbLeftOption   = 0x0700e2;
+const unsigned int kUsbLeftCmd      = 0x0700e3;
+const unsigned int kUsbRightControl = 0x0700e4;
+const unsigned int kUsbRightShift   = 0x0700e5;
+const unsigned int kUsbRightOption  = 0x0700e6;
+const unsigned int kUsbRightCmd     = 0x0700e7;
+const unsigned int kUsbTab          = 0x07002b;
 
 }  // namespace
 
@@ -28,19 +32,32 @@ MacKeyEventProcessor::~MacKeyEventProcessor() {
 }
 
 void MacKeyEventProcessor::InjectKeyEvent(const protocol::KeyEvent& event) {
-  if (event.pressed()) {
-    key_pressed_map_[event.keycode()] = event;
-  } else {
-    key_pressed_map_.erase(event.keycode());
-    if (event.keycode() == kLeftCmd || event.keycode() == kRightCmd)
-      GenerateKeyupEvents();
+  DCHECK(event.has_usb_keycode());
+
+  bool is_special_key = event.usb_keycode() == kUsbLeftControl ||
+      event.usb_keycode() == kUsbLeftShift ||
+      event.usb_keycode() == kUsbLeftOption ||
+      event.usb_keycode() == kUsbRightControl ||
+      event.usb_keycode() == kUsbRightShift ||
+      event.usb_keycode() == kUsbRightOption ||
+      event.usb_keycode() == kUsbTab;
+
+  bool is_cmd_key = event.usb_keycode() == kUsbLeftCmd ||
+      event.usb_keycode() == kUsbRightCmd;
+
+  if (!is_cmd_key && !is_special_key) {
+    if (event.pressed()) {
+      key_pressed_map_[event.usb_keycode()] = event;
+    } else {
+      key_pressed_map_.erase(event.usb_keycode());
+    }
   }
 
-  InputFilter::InjectKeyEvent(event);
-}
+  if (is_cmd_key && !event.pressed()) {
+    GenerateKeyupEvents();
+  }
 
-int MacKeyEventProcessor::NumberOfPressedKeys() const {
-  return key_pressed_map_.size();
+  InputFilter::InjectKeyEvent(event);
 }
 
 void MacKeyEventProcessor::GenerateKeyupEvents() {
@@ -52,12 +69,6 @@ void MacKeyEventProcessor::GenerateKeyupEvents() {
        i != key_pressed_map_.end(); ++i) {
     const int keycode = i->first;
 
-    if (keycode == kCapsLock || keycode == kOption ||
-        keycode == kControl || keycode == kShift ||
-        keycode == kLeftCmd || keycode == kRightCmd) {
-      continue;
-    }
-
     keycodes.push_back(keycode);
     protocol::KeyEvent event = i->second;
     event.set_pressed(false);

remoting/client/plugin/mac_key_event_processor.h

@@ -12,13 +12,6 @@
 // The cause is that CMD + C triggers a system action and Chrome injects only a
 // keydown event for the C key. Safari shares the same behavior.
 //
-// This is a list of sample edge cases:
-//
-// CMD DOWN, C DOWN, C UP, CMD UP
-// CMD DOWN, SHIFT DOWN, C DOWN, C UP, CMD UP, SHIFT UP
-// CMD DOWN, CAPS LOCK DOWN, CMD DOWN, CAPS LOCK DOWN
-// L CMD DOWN, C DOWN, R CMD DOWN, L CMD UP, C UP, R CMD UP
-//
 // SOLUTION
 //
 // When a keyup event for CMD key happens we will check all prior keydown
@@ -41,7 +34,8 @@
 // CMD DOWN, C DOWN, C UP, CMD UP, C UP
 //
 // Because we artificially generate keyup events the C UP event is duplicated
-// as user releases the key after CMD key.
+// as user releases the key after CMD key. This would not be a problem as the
+// receiver end will drop this duplicated keyup event.
 
 #ifndef REMOTING_CLIENT_PLUGIN_MAC_KEY_EVENT_PROCESSOR_H_
 #define REMOTING_CLIENT_PLUGIN_MAC_KEY_EVENT_PROCESSOR_H_
@@ -66,12 +60,8 @@ class MacKeyEventProcessor : public protocol::InputFilter {
   // InputFilter overrides.
   virtual void InjectKeyEvent(const protocol::KeyEvent& event) OVERRIDE;
 
-  // Return the number of keys pressed. This method is used by unit test to
-  // test correctness of this class.
-  int NumberOfPressedKeys() const;
-
  private:
-  // Iterate the current pressed keys and generate keyup events.
+  // Generate keyup events for any keys pressed with CMD.
   void GenerateKeyupEvents();
 
   // A map that stores pressed keycodes and the corresponding key event.