Use KotlinLexer to determine the correct offset of an infix operator
token instead of skipping whitespaces after the operator's LHS.
This fixes cases like this:
```
assert("Name"/*in*/in/*in*/listOf("Hello", "World"))
| |
| [Hello, World]
false
```
Instead of searching for the operator in the string representation of
the whole expression, consider the operator's start to be the
first non-whitespace non-dot character _after_ the LHS of the infix
expression.
This fixes cases like this:
```
assert("Name in " in listOf("Hello", "World"))
| |
| [Hello, World]
false
```
^KT-66208 Fixed
Calls of infix functions have a start offset which doesn't include the
receiver. Property accessors have a start offset at the start of the
property name and do not include their receiver expression. This
combination can cause problems when the entire expression needs to be
displayed, including the entirety of a complex receiver. Make sure to
navigate expressions to find their earliest starting offset and use that
instead.
^KT-65810 Fixed