Update NOPRESUBMIT docs.

site/dev/contrib/cqkeywords.md

 Commit Queue Keywords
 =====================
 
 COMMIT
 ------
 
 If you are working on experimental code and do not want to risk accidentally
 submitting the change via the CQ, then you can mark it with "COMMIT=false".
 The CQ will immediately abandon the change if it contains this option.
 To do a dry run through the CQ please use Rietveld's [dry run](https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/G5-X0_tfmok) feature.
 
     COMMIT=false
 
-The CQ will run through its list of verifiers (reviewer check, trybots, tree check, 
+The CQ will run through its list of verifiers (reviewer check, trybots, tree check,
 presubmit check), and will close the issue instead of committing it.
 
 NO_DEPENDENCY_CHECKS
 --------------------
 
     NO_DEPENDENCY_CHECKS=true
 
 The CQ rejects patchsets with open dependencies. An open dependency exists when a CL
 depends on another CL that is not yet closed. You can skip this check with this keyword.
 
 CQ_INCLUDE_TRYBOTS
 ------------------
 
-Allows you to add arbitrary trybots to the CQ's list of default trybots. 
+Allows you to add arbitrary trybots to the CQ's list of default trybots.
 The CQ will block till these tryjobs pass just like the default list of tryjobs.
 
 This is the format of the values of this keyword:
 
     CQ_INCLUDE_TRYBOTS=master1:bot1,bot2;master2:bot3,bot4
 
 Here are some real world examples:
 
     CQ_INCLUDE_TRYBOTS=tryserver.chromium:linux_layout_rel
 
     CQ_INCLUDE_TRYBOTS=tryserver.skia:Build-Mac10.9-Clang-x86_64-Debug
 
 CQ_EXCLUDE_TRYBOTS
 ------------------
 
-Allows you to remove trybots from the CQ's list of default trybots. Should only be 
+Allows you to remove trybots from the CQ's list of default trybots. Should only be
 used when particular builders are failing for reasons unrelated to your code changes.
 
 This is the format of the values of this keyword:
 
     CQ_EXCLUDE_TRYBOTS=master1:bot1,bot2;master2:bot3,bot4
 
 Here are some real world examples:
 
     CQ_EXCLUDE_TRYBOTS=tryserver.chromium:win_chromium_compile_dbg
 
     CQ_EXCLUDE_TRYBOTS=tryserver.skia:Build-Win7-VS2010-x86-Debug-Trybot
 
 CQ_TRYBOTS
 ----------
 
 Allows you to list every trybot that you want to run for your CL.
 
 This is the format of the values of this keyword:
 
     CQ_TRYBOTS=master1:bot1,bot2;master2:bot3,bot4
 
 Here are some real world examples:
 
     CQ_TRYBOTS=tryserver.chromium:linux_chromium_gn_rel,linux_chromium_chromeos_rel,
       android_dbg_triggered_tests,android_dbg,mac_chromium_rel,win_chromium_x64_rel
 
     CQ_TRYBOTS=tryserver.skia:Build-Win7-VS2010-x86-Debug-Trybot,
       Test-Ubuntu13.10-ShuttleA-NoGPU-x86_64-Debug-Trybot,
       Build-Ubuntu13.10-GCC4.8-x86_64-Release-Trybot,
-      Build-Ubuntu13.10-Clang-x86_64-Debug-Trybot,Build-Mac10.8-Clang-x86_64-Release-Trybot 
+      Build-Ubuntu13.10-Clang-x86_64-Debug-Trybot,Build-Mac10.8-Clang-x86_64-Release-Trybot
 
 TBR
 ---
 
-If you are a Skia committer and cannot wait for a review, 
+If you are a Skia committer and cannot wait for a review,
 then you can include the TBR keyword in your CL's description.
 
 Example:
 
     TBR=rmistry@google.com
 
 NOTREECHECKS
 ------------
 
-If you want to skip the tree status checks, to make the CQ commit a CL even if the tree is closed, 
+If you want to skip the tree status checks, to make the CQ commit a CL even if the tree is closed,
 you can add the following line to the CL description:
 
     NOTREECHECKS=true
 
-This is discouraged, since the tree is closed for a reason. However, in rare cases this is acceptable, 
+This is discouraged, since the tree is closed for a reason. However, in rare cases this is acceptable,
 primarily to fix build breakages (i.e., your CL will help in reopening the tree).
 
-NOPRESUBMIT
+CQ_EXCLUDE_TRYBOTS=client.skia.fyi:skia_presubmit-Trybot (née NOPRESUBMIT)
 -----------
 
 If you want to skip the presubmit checks, add the following line to the CL description:
 
-    NOPRESUBMIT=true
+    CQ_EXCLUDE_TRYBOTS=client.skia.fyi:skia_presubmit-Trybot
 
 NOTRY
 -----
 
 If you cannot wait for the try job results, you can add the following line to the CL description:
 
     NOTRY=true
 
 The CQ will then not run any try jobs for your change and will commit the CL as soon as the tree is open, assuming the presubmit check passes.
 
 NO_MERGE_BUILDS
 ---------------
 
 This keyword prevents the Skia build masters from building this commit with others. Use it when your
 commit may have effects that you don't want mis-attributed to other commits. Just include the keyword
 somewhere in the commit message:
 
     NO_MERGE_BUILDS