Remove unused msaa flag description variables

Followup to:
https://chromium-review.googlesource.com/c/chromium/src/+/1342938

Change-Id: I8721e0acfcaafddf2c3b49c7752c5c6b4d498281
Reviewed-on: https://chromium-review.googlesource.com/c/1343288Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609460}

chrome/browser/flag_descriptions.cc

@@ -1065,16 +1065,6 @@ const char kGamepadVibrationName[] = "Gamepad Vibration";
 const char kGamepadVibrationDescription[] =
     "Enables haptic vibration effects on supported gamepads.";
 
-const char kGpuRasterizationMsaaSampleCountName[] =
-    "GPU rasterization MSAA sample count.";
-const char kGpuRasterizationMsaaSampleCountDescription[] =
-    "Specify the number of MSAA samples for GPU rasterization.";
-const char kGpuRasterizationMsaaSampleCountZero[] = "0";
-const char kGpuRasterizationMsaaSampleCountTwo[] = "2";
-const char kGpuRasterizationMsaaSampleCountFour[] = "4";
-const char kGpuRasterizationMsaaSampleCountEight[] = "8";
-const char kGpuRasterizationMsaaSampleCountSixteen[] = "16";
-
 const char kGpuRasterizationName[] = "GPU rasterization";
 const char kGpuRasterizationDescription[] =
     "Use GPU to rasterize web content. Requires impl-side painting.";

chrome/browser/flag_descriptions.h

@@ -650,14 +650,6 @@ extern const char kGamepadExtensionsDescription[];
 extern const char kGamepadVibrationName[];
 extern const char kGamepadVibrationDescription[];
 
-extern const char kGpuRasterizationMsaaSampleCountName[];
-extern const char kGpuRasterizationMsaaSampleCountDescription[];
-extern const char kGpuRasterizationMsaaSampleCountZero[];
-extern const char kGpuRasterizationMsaaSampleCountTwo[];
-extern const char kGpuRasterizationMsaaSampleCountFour[];
-extern const char kGpuRasterizationMsaaSampleCountEight[];
-extern const char kGpuRasterizationMsaaSampleCountSixteen[];
-
 extern const char kGpuRasterizationName[];
 extern const char kGpuRasterizationDescription[];
 extern const char kForceGpuRasterization[];