Remove "--shared-array-buffer" flag

It has been enabled by default on desktop for a while now. The feature
is still required, since SharedArrayBuffer is still not enabled by
default on Android.

Bug: 821270
Change-Id: Ie58c4bb4118648391f533f310a8f093f9fa4e19b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015564Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Ben Smith <binji@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734576}

chrome/browser/about_flags.cc

@@ -1704,9 +1704,6 @@ const FeatureEntry kFeatureEntries[] = {
     {"enable-webassembly-tiering", flag_descriptions::kEnableWasmTieringName,
      flag_descriptions::kEnableWasmTieringDescription, kOsAll,
      FEATURE_VALUE_TYPE(features::kWebAssemblyTiering)},
-    {"shared-array-buffer", flag_descriptions::kEnableSharedArrayBufferName,
-     flag_descriptions::kEnableSharedArrayBufferDescription, kOsAll,
-     FEATURE_VALUE_TYPE(features::kSharedArrayBuffer)},
     {"enable-future-v8-vm-features", flag_descriptions::kV8VmFutureName,
      flag_descriptions::kV8VmFutureDescription, kOsAll,
      FEATURE_VALUE_TYPE(features::kV8VmFuture)},

chrome/browser/flag-metadata.json

@@ -3191,11 +3191,6 @@
     // have no access to commandline flags.
     "expiry_milestone": -1
   },
-  {
-    "name": "shared-array-buffer",
-    "owners": [ "binji" ],
-    "expiry_milestone": 78
-  },
   {
     "name": "shared-clipboard-receiver",
     "owners": [ "//chrome/browser/sharing/OWNERS" ],

chrome/browser/flag_descriptions.cc

@@ -937,11 +937,6 @@ const char kEnableScrollAnchorSerializationDescription[] =
     "Save the scroll anchor and use it to restore the scroll position when "
     "navigating.";
 
-const char kEnableSharedArrayBufferName[] =
-    "Experimental enabled SharedArrayBuffer support in JavaScript.";
-const char kEnableSharedArrayBufferDescription[] =
-    "Enable SharedArrayBuffer support in JavaScript.";
-
 const char kEnableSubresourceRedirectName[] =
     "Enable Render Level Data Use Optimization";
 const char kEnableSubresourceRedirectDescription[] =
@@ -984,8 +979,7 @@ const char kEnableWasmSimdDescription[] =
 
 const char kEnableWasmThreadsName[] = "WebAssembly threads support";
 const char kEnableWasmThreadsDescription[] =
-    "Enables support for the WebAssembly Threads proposal. Implies "
-    "#shared-array-buffer and #enable-webassembly.";
+    "Enables support for the WebAssembly Threads proposal.";
 
 const char kEnableWasmTieringName[] = "WebAssembly tiering";
 const char kEnableWasmTieringDescription[] =

chrome/browser/flag_descriptions.h

@@ -561,9 +561,6 @@ extern const char kEnableUseZoomForDsfChoiceDisabled[];
 extern const char kEnableScrollAnchorSerializationName[];
 extern const char kEnableScrollAnchorSerializationDescription[];
 
-extern const char kEnableSharedArrayBufferName[];
-extern const char kEnableSharedArrayBufferDescription[];
-
 extern const char kEnableWasmName[];
 extern const char kEnableWasmDescription[];