Fix gamepad mapping for Shield and Xbox controllers

content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java

Index: content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java b/content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java
index 5fe418f4eeb060369d4bd573ccafbf1c716d0ea7..f0c14d1ae88a60f248475173fe0d2d4876ca11e1 100644
--- a/content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java
+++ b/content/public/android/java/src/org/chromium/content/browser/input/GamepadMappings.java
@@ -75,6 +75,13 @@ class GamepadMappings {
         mappedButtons[CanonicalButtonIndex.RIGHT_TRIGGER] = r1;
     }
 
+    private static void mapTriggerButtonsToTopShoulder(float[] mappedButtons, float[] rawButtons) {
+        float l1 = rawButtons[KeyEvent.KEYCODE_BUTTON_L1];
+        float r1 = rawButtons[KeyEvent.KEYCODE_BUTTON_R1];
+        mappedButtons[CanonicalButtonIndex.LEFT_SHOULDER] = l1;
+        mappedButtons[CanonicalButtonIndex.RIGHT_SHOULDER] = r1;
+    }
+
     private static void mapCommonDpadButtons(float[] mappedButtons, float[] rawButtons) {
         float dpadDown = rawButtons[KeyEvent.KEYCODE_DPAD_DOWN];
         float dpadUp = rawButtons[KeyEvent.KEYCODE_DPAD_UP];
@@ -108,6 +115,13 @@ class GamepadMappings {
         mappedButtons[CanonicalButtonIndex.RIGHT_SHOULDER] = rTrigger;
     }
 
+    private static void mapTriggerAxesToBottomShoulder(float[] mappedButtons, float[] rawAxes) {
+        float lTrigger = rawAxes[MotionEvent.AXIS_LTRIGGER];
+        float rTrigger = rawAxes[MotionEvent.AXIS_RTRIGGER];
+        mappedButtons[CanonicalButtonIndex.LEFT_TRIGGER] = lTrigger;
+        mappedButtons[CanonicalButtonIndex.RIGHT_TRIGGER] = rTrigger;
+    }
+
     private static float negativeAxisValueAsButton(float input) {
         return (input < -0.5f) ? 1.f : 0.f;
     }
@@ -132,10 +146,10 @@ class GamepadMappings {
     private static void mapShieldGamepad(float[] mappedButtons, float[] rawButtons,
             float[] mappedAxes, float[] rawAxes) {
         mapCommonXYABButtons(mappedButtons, rawButtons);
-        mapCommonTriggerButtons(mappedButtons, rawButtons);
+        mapTriggerButtonsToTopShoulder(mappedButtons, rawButtons);
         mapCommonThumbstickButtons(mappedButtons, rawButtons);
         mapCommonStartSelectMetaButtons(mappedButtons, rawButtons);
-        mapTriggerAxexToShoulderButtons(mappedButtons, rawAxes);
+        mapTriggerAxesToBottomShoulder(mappedButtons, rawAxes);
         mapHatAxisToDpadButtons(mappedButtons, rawAxes);
 
         mapXYAxes(mappedAxes, rawAxes);