Revert "Clang: enable -instcombine-lower-dbg-declare=1"

This reverts commit 32750c1251012624a87fb97098bd0f6a60ffa8ed.

Reason for revert: This CL breaks most of the informational builds https://uberchromegw.corp.google.com/i/chromeos.chrome/waterfall?reload=300. See an example here: https://uberchromegw.corp.google.com/i/chromeos.chrome/builders/veyron_minnie-tot-chrome-pfq-informational/builds/6039

Original change's description:
> Clang: enable -instcombine-lower-dbg-declare=1
> 
> This enables better optimized debug info for address-taken values
> at the cost of potentially inaccurate debug info in some situations.
> 
> We believe turning this on is the right trade-off for developers
> debugging Chromium on all platforms, but especially on Windows where
> values that are available in MSVC's debug info would otherwise show
> as unavailable when using Clang.
> 
> The goal (crbug.com/765793) is to make Clang's optimized
> debug info good enough in all cases that this compromise is not
> necessary.
> 
> Note: This requires Clang r313108 or later.
> 
> Bug: 761633, 753736, 765793
> Change-Id: Ia0ed38c499fac282a3c8ab27c5fd5571fdfab84d
> Reviewed-on: https://chromium-review.googlesource.com/669314
> Commit-Queue: Hans Wennborg <hans@chromium.org>
> Reviewed-by: Nico Weber <thakis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#502428}

TBR=thakis@chromium.org,hans@chromium.org,rnk@chromium.org

Change-Id: I4fea2ab8ec9571d4afb66cd3912c5975e0b9395c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 761633, 753736, 765793
Reviewed-on: https://chromium-review.googlesource.com/669825
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#502484}
1 file changed