feat: Added default Leave Approver in Employee (#18953)

diff --git a/erpnext/hr/doctype/employee/employee.json b/erpnext/hr/doctype/employee/employee.json
index 5202218..ee0b2a2 100644
--- a/erpnext/hr/doctype/employee/employee.json
+++ b/erpnext/hr/doctype/employee/employee.json
@@ -7,6 +7,7 @@
  "doctype": "DocType",
  "document_type": "Setup",
  "editable_grid": 1,
+ "engine": "InnoDB",
  "field_order": [
   "basic_information",
   "employee",
@@ -54,6 +55,7 @@
   "column_break_44",
   "holiday_list",
   "default_shift",
+  "leave_approver",
   "salary_information",
   "salary_mode",
   "bank_name",
@@ -767,12 +769,18 @@
    "fieldtype": "Link",
    "label": "Default Shift",
    "options": "Shift Type"
+  },
+  {
+   "fieldname": "leave_approver",
+   "fieldtype": "Link",
+   "label": "Leave Approver",
+   "options": "User"
   }
  ],
  "icon": "fa fa-user",
  "idx": 24,
  "image_field": "image",
- "modified": "2019-06-01 16:05:55.132180",
+ "modified": "2019-09-06 15:54:36.735147",
  "modified_by": "Administrator",
  "module": "HR",
  "name": "Employee",
diff --git a/erpnext/hr/doctype/leave_application/leave_application.py b/erpnext/hr/doctype/leave_application/leave_application.py
index 0aa8849..d4da9c1 100755
--- a/erpnext/hr/doctype/leave_application/leave_application.py
+++ b/erpnext/hr/doctype/leave_application/leave_application.py
@@ -745,10 +745,12 @@
 	return leave_days
 
 @frappe.whitelist()
-def get_leave_approver(employee, department=None):
-	if not department:
-		department = frappe.db.get_value('Employee', employee, 'department')
+def get_leave_approver(employee):
+	leave_approver, department = frappe.db.get_value("Employee",
+		employee, ["leave_approver", "department"])
 
-	if department:
-		return frappe.db.get_value('Department Approver', {'parent': department,
-			'parentfield': 'leave_approvers', 'idx': 1}, 'approver')
\ No newline at end of file
+	if not leave_approver and department:
+		leave_approver = frappe.db.get_value('Department Approver', {'parent': department,
+			'parentfield': 'leave_approvers', 'idx': 1}, 'approver')
+
+	return leave_approver
\ No newline at end of file