Convert DCHECKs to CHECKs for histogram types

Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org

Committed: https://crrev.com/03c2e97746a2c471ae136b0c669f8d0c033fe168
Cr-Commit-Position: refs/heads/master@{#421929}

[kenrb, 2016-09-29 17:30:49]

Ilya: PTAL?

I just cc'd you on the bug so you can see the context.

[Ilya Sherman, 2016-09-29 18:32:26]

LGTM, thanks.

[kenrb, 2016-09-29 18:34:14]

Description was changed from

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org
==========

to

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org
==========

[kenrb, 2016-09-29 18:34:18]

The CQ bit was checked by kenrb@chromium.org

[commit-bot: I haz the power, 2016-09-29 18:34:40]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-29 20:51:23]

Description was changed from

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org
==========

to

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org
==========

[commit-bot: I haz the power, 2016-09-29 20:51:24]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-29 20:55:23]

Description was changed from

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org
==========

to

==========
Convert DCHECKs to CHECKs for histogram types

When a histogram is looked up by name, there is currently a DCHECK that
verifies the type of the stored histogram matches the expected type.

A mismatch represents a significant problem because the returned
HistogramBase is cast to a Histogram in ValidateRangeChecksum,
potentially causing a crash.

This CL converts the DCHECK to a CHECK to prevent the possibility of
type confusion in release builds.

BUG=651443
R=isherman@chromium.org

Committed: https://crrev.com/03c2e97746a2c471ae136b0c669f8d0c033fe168
Cr-Commit-Position: refs/heads/master@{#421929}
==========

[commit-bot: I haz the power, 2016-09-29 20:55:24]

Patchset 1 (id:??) landed as
https://crrev.com/03c2e97746a2c471ae136b0c669f8d0c033fe168
Cr-Commit-Position: refs/heads/master@{#421929}