Prefix build variables used in separate repos with mojo_

As requested by Brett here:
https://codereview.chromium.org/1029113005/diff/20001/build/module_args/mojo.gni

R=blundell@chromium.org, viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/1034603002
diff --git a/mojo/BUILD.gn b/mojo/BUILD.gn
index ca646cd..18d0158 100644
--- a/mojo/BUILD.gn
+++ b/mojo/BUILD.gn
@@ -79,7 +79,7 @@
     deps += [ "//services/python:python_apptests" ]
   }
 
-  if (use_prebuilt_network_service) {
+  if (mojo_use_prebuilt_network_service) {
     deps += [ "//mojo/public/tools:copy_network_service_apptests" ]
   }
 }
diff --git a/mojo/public/mojo.gni b/mojo/public/mojo.gni
index b8676e6..f2631a0 100644
--- a/mojo/public/mojo.gni
+++ b/mojo/public/mojo.gni
@@ -6,23 +6,25 @@
 
 # If using the prebuilt shell, gate its usage by the platforms for which it is
 # published.
-use_prebuilt_mojo_shell = false
-if (!defined(build_mojo_shell_from_source) || !build_mojo_shell_from_source) {
-  use_prebuilt_mojo_shell = is_linux || is_android
+mojo_use_prebuilt_mojo_shell = false
+if (!defined(mojo_build_mojo_shell_from_source) ||
+    !mojo_build_mojo_shell_from_source) {
+  mojo_use_prebuilt_mojo_shell = is_linux || is_android
 }
 
 # If using the prebuilt network service, gate its usage by the platforms for
 # which it is published.
-use_prebuilt_network_service = false
-if (!defined(build_network_service_from_source) ||
-    !build_network_service_from_source) {
-  use_prebuilt_network_service = is_linux || is_android
+mojo_use_prebuilt_network_service = false
+if (!defined(mojo_build_network_service_from_source) ||
+    !mojo_build_network_service_from_source) {
+  mojo_use_prebuilt_network_service = is_linux || is_android
 }
 
 # Enable Dart apptest framework by default.
-use_dart_apptest_framework = true
-if (defined(disable_dart_apptest_framework) && disable_dart_apptest_framework) {
-  use_dart_apptest_framework = false
+mojo_use_dart_apptest_framework = true
+if (defined(mojo_disable_dart_apptest_framework) &&
+    mojo_disable_dart_apptest_framework) {
+  mojo_use_dart_apptest_framework = false
 }
 
 # The absolute path to the directory containing the mojo public SDK (i.e., the
diff --git a/mojo/public/mojo_application.gni b/mojo/public/mojo_application.gni
index ce8cf9e..2c7ee4a 100644
--- a/mojo/public/mojo_application.gni
+++ b/mojo/public/mojo_application.gni
@@ -77,11 +77,11 @@
       }
 
       # Copy any necessary prebuilt artifacts.
-      if (use_prebuilt_mojo_shell) {
+      if (mojo_use_prebuilt_mojo_shell) {
         data_deps +=
             [ rebase_path("mojo/public/tools:copy_mojo_shell", ".", mojo_root) ]
       }
-      if (use_prebuilt_network_service) {
+      if (mojo_use_prebuilt_network_service) {
         data_deps += [ rebase_path("mojo/public/tools:copy_network_service",
                                    ".",
                                    mojo_root) ]
@@ -197,11 +197,11 @@
       }
 
       # Copy any necessary prebuilt artifacts.
-      if (use_prebuilt_mojo_shell) {
+      if (mojo_use_prebuilt_mojo_shell) {
         data_deps +=
             [ rebase_path("mojo/public/tools:copy_mojo_shell", ".", mojo_root) ]
       }
-      if (use_prebuilt_network_service) {
+      if (mojo_use_prebuilt_network_service) {
         data_deps += [ rebase_path("mojo/public/tools:copy_network_service",
                                    ".",
                                    mojo_root) ]
diff --git a/mojo/public/tools/BUILD.gn b/mojo/public/tools/BUILD.gn
index b5cfcd4..9344cf3 100644
--- a/mojo/public/tools/BUILD.gn
+++ b/mojo/public/tools/BUILD.gn
@@ -5,7 +5,7 @@
 import("//build/module_args/mojo.gni")
 import("../mojo.gni")
 
-if (use_prebuilt_mojo_shell) {
+if (mojo_use_prebuilt_mojo_shell) {
   copy("copy_mojo_shell") {
     filename = "mojo_shell"
     if (is_android) {
@@ -28,13 +28,13 @@
   }
 }
 
-if (use_prebuilt_network_service) {
+if (mojo_use_prebuilt_network_service) {
   copy("copy_network_service") {
     filename = "network_service.mojo"
-    if (defined(prebuilt_network_service_location) &&
-        prebuilt_network_service_location != "") {
+    if (defined(mojo_prebuilt_network_service_location) &&
+        mojo_prebuilt_network_service_location != "") {
       sources = [
-        "$prebuilt_network_service_location",
+        "$mojo_prebuilt_network_service_location",
       ]
     } else {
       if (is_android) {
@@ -78,7 +78,7 @@
 # loaded from Google Storage and then puts it in a rule which the
 # "dart_package" template in mojo/public/dart/rules.gni can introspect on,
 # accessing the 'label' and 'target_out_dir' variables.
-if (use_dart_apptest_framework) {
+if (mojo_use_dart_apptest_framework) {
   copy("dart_apptest_framework") {
     sources = [
       "prebuilt/frameworks/apptest.dartzip",
diff --git a/mojo/services/content_handler/public/interfaces/BUILD.gn b/mojo/services/content_handler/public/interfaces/BUILD.gn
index 77798ea..c58507a 100644
--- a/mojo/services/content_handler/public/interfaces/BUILD.gn
+++ b/mojo/services/content_handler/public/interfaces/BUILD.gn
@@ -12,14 +12,14 @@
 
   import_dirs = [ get_path_info("../../../", "abspath") ]
 
-  if (defined(network_service_root)) {
-    import_dirs += [ network_service_root ]
+  if (defined(mojo_network_service_root)) {
+    import_dirs += [ mojo_network_service_root ]
   } else {
-    network_service_root = "../../.."
+    mojo_network_service_root = "../../.."
   }
 
   deps = [
-    "$network_service_root/network/public/interfaces",
+    "$mojo_network_service_root/network/public/interfaces",
   ]
 
   mojo_sdk_deps = [ "mojo/public/interfaces/application" ]
diff --git a/mojo/services/http_server/public/interfaces/BUILD.gn b/mojo/services/http_server/public/interfaces/BUILD.gn
index 7fde891..79aa6a6 100644
--- a/mojo/services/http_server/public/interfaces/BUILD.gn
+++ b/mojo/services/http_server/public/interfaces/BUILD.gn
@@ -15,13 +15,13 @@
 
   import_dirs = [ get_path_info("../../../", "abspath") ]
 
-  if (defined(network_service_root)) {
-    import_dirs += [ network_service_root ]
+  if (defined(mojo_network_service_root)) {
+    import_dirs += [ mojo_network_service_root ]
   } else {
-    network_service_root = "../../.."
+    mojo_network_service_root = "../../.."
   }
 
   deps = [
-    "$network_service_root/network/public/interfaces",
+    "$mojo_network_service_root/network/public/interfaces",
   ]
 }
diff --git a/mojo/services/navigation/public/interfaces/BUILD.gn b/mojo/services/navigation/public/interfaces/BUILD.gn
index 5141680..19b9f8a 100644
--- a/mojo/services/navigation/public/interfaces/BUILD.gn
+++ b/mojo/services/navigation/public/interfaces/BUILD.gn
@@ -12,13 +12,13 @@
 
   import_dirs = [ get_path_info("../../../", "abspath") ]
 
-  if (defined(network_service_root)) {
-    import_dirs += [ network_service_root ]
+  if (defined(mojo_network_service_root)) {
+    import_dirs += [ mojo_network_service_root ]
   } else {
-    network_service_root = "../../.."
+    mojo_network_service_root = "../../.."
   }
 
   deps = [
-    "$network_service_root/network/public/interfaces",
+    "$mojo_network_service_root/network/public/interfaces",
   ]
 }