dartc does not check for _ in named parameters

[DartBot]

This issue was originally filed by zundel@google.com

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It is a compile time error if a named formal parameter begins with an _

See co19 test Language/06_Functions/2_Formal_Parameters/2_Named_Optional_Formals_A03_t01

See also issue #2137

[kasperl]

Removed Area-Compiler label.
Added Area-Analyzer label.

[danrubel]

Added this to the M1 milestone.

[DartBot]

This comment was originally written by zundel@google.com

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Set owner to zundel@google.com.

[DartBot]

This comment was originally written by zundel@google.com

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Filed issue #3496 as tthere is at least one method in the dartium library that uses an underscore, causing compiling lots of existing code to break

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Marked this as being blocked by #3496.

[DartBot]

This comment was originally written by zundel@google.com

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https://chromiumcodereview.appspot.com/10541095

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Added Started label.

[DartBot]

This comment was originally written by zundel@google.com

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r8631

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Added Fixed label.