update a few bot packages

Most interesting thing ought to be that we get
-fsanitize=implicit-conversion via -fsanitize=integer now on Linux.

As far as I can tell, this should be a lot like /RTCc that we use
on our msvs.analyze config.

(https://docs.microsoft.com/en-us/cpp/build/reference/rtc-run-time-error-checks?view=vs-2017)

The bot's not failing, so I just tried it out locally:

  ~ $ cat test.c
  #include <stdlib.h>
  int main(int argc, char** argv) {
      char c = argc > 1 ? atoi(argv[1]) : 42;
      return c % 2;
  }
  ~ $ clang -fsanitize=integer test.c
  ~ $ ./a.out 127
  ~ $ ./a.out 128
  test.c:3:14: runtime error: implicit conversion from type 'int' of value 128 (32-bit, signed) to type 'char' changed the value to -128 (8-bit, signed)
  ~ $ ./a.out -128
  ~ $ ./a.out -129
  test.c:3:14: runtime error: implicit conversion from type 'int' of value -129 (32-bit, signed) to type 'char' changed the value to 127 (8-bit, signed)

Change-Id: I3640adb4e2ff9243055f2f638b754b16c5c87e75
Reviewed-on: https://skia-review.googlesource.com/156250
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/infra/bots/gen_tasks.go b/infra/bots/gen_tasks.go
index 3c68e2f..6619bcf 100644
--- a/infra/bots/gen_tasks.go
+++ b/infra/bots/gen_tasks.go
@@ -39,7 +39,7 @@
 			&specs.CipdPackage{
 				Name:    "skia/bots/clang_linux",
 				Path:    "clang_linux",
-				Version: "version:11",
+				Version: "version:12",
 			},
 		},
 		"skcms-Mac": []*specs.CipdPackage{
@@ -77,7 +77,7 @@
 			&specs.CipdPackage{
 				Name:    "skia/bots/clang_win",
 				Path:    "clang_win",
-				Version: "version:6",
+				Version: "version:7",
 			},
 		},
 	}
diff --git a/infra/bots/tasks.json b/infra/bots/tasks.json
index d5c540f..a2bf08d 100644
--- a/infra/bots/tasks.json
+++ b/infra/bots/tasks.json
@@ -39,7 +39,7 @@
         {
           "name": "skia/bots/clang_linux",
           "path": "clang_linux",
-          "version": "version:11"
+          "version": "version:12"
         }
       ],
       "command": [
@@ -115,7 +115,7 @@
         {
           "name": "skia/bots/clang_win",
           "path": "clang_win",
-          "version": "version:6"
+          "version": "version:7"
         }
       ],
       "command": [