Remove duplicated switch allow-pre-commit-input

The switch allow-pre-commit-input was moved from //content to
//third_party/blink in the change
https://chromium-review.googlesource.com/c/chromium/src/+/2232804/.
But accidentally it was back to the //content in the change
https://chromium-review.googlesource.com/c/chromium/src/+/2225528/
between patchsets 10 and 11.

Bug: 1073560
Change-Id: I712d6df7786d26590872efc1b5fcdd96d046dd63
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2537701Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Juanmi Huertas <juanmihd@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827415}

content/public/common/content_switches.cc

@@ -9,11 +9,6 @@
 
 namespace switches {
 
-// Allows processing of input before a frame has been committed.
-// TODO(schenney): crbug.com/987626. Used by headless. Look for a way not
-// involving a command line switch.
-const char kAllowPreCommitInput[] = "allow-pre-commit-input";
-
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
 const char kAllowFileAccessFromFiles[]      = "allow-file-access-from-files";

content/public/common/content_switches.h

@@ -15,7 +15,6 @@ namespace switches {
 
 // All switches in alphabetical order. The switches should be documented
 // alongside the definition of their values in the .cc file.
-CONTENT_EXPORT extern const char kAllowPreCommitInput[];
 CONTENT_EXPORT extern const char kAllowFileAccessFromFiles[];
 CONTENT_EXPORT extern const char kAllowInsecureLocalhost[];
 CONTENT_EXPORT extern const char kAllowLoopbackInPeerConnection[];