Convert gn docstrings to C++11 raw strings.

tools/gn/function_set_default_toolchain.cc

Index: tools/gn/function_set_default_toolchain.cc
diff --git a/tools/gn/function_set_default_toolchain.cc b/tools/gn/function_set_default_toolchain.cc
index cc5929e6686a4d1de95cc2494738d40f6ea8f6f9..b9d31099cdb8b052a8fa13f8bd24dd2b5e4c6655 100644
--- a/tools/gn/function_set_default_toolchain.cc
+++ b/tools/gn/function_set_default_toolchain.cc
@@ -15,33 +15,33 @@ const char kSetDefaultToolchain[] = "set_default_toolchain";
 const char kSetDefaultToolchain_HelpShort[] =
     "set_default_toolchain: Sets the default toolchain name.";
 const char kSetDefaultToolchain_Help[] =
-    "set_default_toolchain: Sets the default toolchain name.\n"
-    "\n"
-    "  set_default_toolchain(toolchain_label)\n"
-    "\n"
-    "  The given label should identify a toolchain definition (see\n"
-    "  \"help toolchain\"). This toolchain will be used for all targets\n"
-    "  unless otherwise specified.\n"
-    "\n"
-    "  This function is only valid to call during the processing of the build\n"
-    "  configuration file. Since the build configuration file is processed\n"
-    "  separately for each toolchain, this function will be a no-op when\n"
-    "  called under any non-default toolchains.\n"
-    "\n"
-    "  For example, the default toolchain should be appropriate for the\n"
-    "  current environment. If the current environment is 32-bit and \n"
-    "  somebody references a target with a 64-bit toolchain, we wouldn't\n"
-    "  want processing of the build config file for the 64-bit toolchain to\n"
-    "  reset the default toolchain to 64-bit, we want to keep it 32-bits.\n"
-    "\n"
-    "Argument:\n"
-    "\n"
-    "  toolchain_label\n"
-    "      Toolchain name.\n"
-    "\n"
-    "Example:\n"
-    "\n"
-    "  set_default_toolchain(\"//build/config/win:vs32\")";
+    R"(set_default_toolchain: Sets the default toolchain name.
+
+  set_default_toolchain(toolchain_label)
+
+  The given label should identify a toolchain definition (see "gn help
+  toolchain"). This toolchain will be used for all targets unless otherwise
+  specified.
+
+  This function is only valid to call during the processing of the build
+  configuration file. Since the build configuration file is processed
+  separately for each toolchain, this function will be a no-op when called
+  under any non-default toolchains.
+
+  For example, the default toolchain should be appropriate for the current
+  environment. If the current environment is 32-bit and somebody references a
+  target with a 64-bit toolchain, we wouldn't want processing of the build
+  config file for the 64-bit toolchain to reset the default toolchain to
+  64-bit, we want to keep it 32-bits.
+
+Argument
+
+  toolchain_label
+      Toolchain name.
+
+Example
+
+  set_default_toolchain("//build/config/win:vs32"))";
 
 Value RunSetDefaultToolchain(Scope* scope,
                              const FunctionCallNode* function,