[call x] inside double quotes followed by alnum char breaks subsequent highlighting

[jasonkradams]

** Example Working**

proc hello_world {} {return "Hello World!"}
when HTTP_REQUEST priority 500 {
    # Comments should be green
    if {1} {puts "i should look like this"}
    puts "[call hello_world]"
    if {1} {puts "i am still highlighted properly"}
    # I am green
}

Example Broken

When [call hello_world] is followed by any alpha or numeric character, it causes the following code to appear as though it is quoted string.

proc hello_world {} {return "Hello World!"}
when HTTP_REQUEST priority 500 {
    # Comments should be green
    if {1} {puts "i should look like this"}
    puts "[call hello_world]a"
    if {1} {puts "but now I look like quoted text"}
    # I am brown; and the if statement above 
}