Remove test for capturing screenshots outside the frame

This patch removes a CaptureScreenshotTest.CaptureScreenshotArea
subtest that was testing screenshots extending beyond the frame. This
does not affect the devtools screenshot feature which resizes the frame
to be large enough.

There could be non-chrome users of the devtools api that depend on this
behavior but I think there are not. For example, on a page such as
https://pr.gg/fixedtall.html, capturing pixels outside the frame would
mean the blue fixed div would be in the middle of the screenshot.

Bug: 922706
Change-Id: I8ed1e143bffd08de6e0f2b6ec6d76da93ab1e797
Reviewed-on: https://chromium-review.googlesource.com/c/1435836Reviewed-by: Eric Seckler <eseckler@chromium.org>
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Auto-Submit: Philip Rogers <pdr@chromium.org>
Commit-Queue: Andrey Kosyakov <caseq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#628417}

content/browser/devtools/protocol/devtools_protocol_browsertest.cc

@@ -572,9 +572,6 @@ IN_PROC_BROWSER_TEST_F(CaptureScreenshotTest,
   PlaceAndCaptureBox(kFrameSize, gfx::Size(100, 200), 2.0, 1.);
   PlaceAndCaptureBox(kFrameSize, gfx::Size(100, 200), 0.5, 1.);
 
-  // Ensure that content outside the emulated frame is painted, too.
-  PlaceAndCaptureBox(kFrameSize, gfx::Size(10, 8192), 1.0, 1.);
-
   // Check non-1 device scale factor.
   PlaceAndCaptureBox(kFrameSize, gfx::Size(100, 200), 1.0, 2.);
   // Ensure not emulating device scale factor works.