Create MSan config for Chromium recipe module + add WebRTC MSan recipe.

scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py

Index: scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py
diff --git a/scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py b/scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py
index d9cbb0bd044e25c4de84ea8579b5877a2ec13a0d..68e503ffef0ec0e137c23d8e90cf2e8eb0266628 100644
--- a/scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py
+++ b/scripts/slave/recipe_modules/chromium/chromium_memory_fyi.py
@@ -10,13 +10,7 @@ SPEC = {
   },
   'builders': {
     'Chromium Linux MSan Builder': {
-      'recipe_config': 'chromium_clang',
-      'GYP_DEFINES': {
-        'msan': 1,
-        'msan_track_origins': 0,
-        'use_instrumented_libraries': 1,
-        'instrumented_libraries_jobs': 10,
-      },
+      'recipe_config': 'chromium_msan',
       'chromium_config_kwargs': {
         'BUILD_CONFIG': 'Release',
         'TARGET_BITS': 64,
@@ -27,12 +21,7 @@ SPEC = {
       },
     },
     'Linux MSan Tests': {
-      'recipe_config': 'chromium_clang',
-      'GYP_DEFINES': {
-        # Required on testers to pass the right runtime flags.
-        # TODO(earthdok): make this part of a chromium_msan recipe config.
-        'msan': 1,
-      },
+      'recipe_config': 'chromium_msan',
       'chromium_config_kwargs': {
         'BUILD_CONFIG': 'Release',
         'TARGET_BITS': 64,
@@ -47,12 +36,7 @@ SPEC = {
       },
     },
     'Linux MSan Browser (1)': {
-      'recipe_config': 'chromium_clang',
-      'GYP_DEFINES': {
-        # Required on testers to pass the right runtime flags.
-        # TODO(earthdok): make this part of a chromium_msan recipe config.
-        'msan': 1,
-      },
+      'recipe_config': 'chromium_msan',
       'chromium_config_kwargs': {
         'BUILD_CONFIG': 'Release',
         'TARGET_BITS': 64,
@@ -67,12 +51,7 @@ SPEC = {
       },
     },
     'Linux MSan Browser (2)': {
-      'recipe_config': 'chromium_clang',
-      'GYP_DEFINES': {
-        # Required on testers to pass the right runtime flags.
-        # TODO(earthdok): make this part of a chromium_msan recipe config.
-        'msan': 1,
-      },
+      'recipe_config': 'chromium_msan',
       'chromium_config_kwargs': {
         'BUILD_CONFIG': 'Release',
         'TARGET_BITS': 64,
@@ -87,12 +66,7 @@ SPEC = {
       },
     },
     'Linux MSan Browser (3)': {
-      'recipe_config': 'chromium_clang',
-      'GYP_DEFINES': {
-        # Required on testers to pass the right runtime flags.
-        # TODO(earthdok): make this part of a chromium_msan recipe config.
-        'msan': 1,
-      },
+      'recipe_config': 'chromium_msan',
       'chromium_config_kwargs': {
         'BUILD_CONFIG': 'Release',
         'TARGET_BITS': 64,