WebUI: Remove unnecessary js_module_root flags

These flags aren't needed once Polymer 3 code is fully checked in,
except for cases where import paths don't match the source tree
structure (e.g. Print Preview).

Bug: None
Change-Id: Ie040cbb7498afc0aa2ec847b0993f6fcaac9aed7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2303308Reviewed-by: dpapad <dpapad@chromium.org>
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#789693}

chrome/browser/resources/extensions/BUILD.gn

@@ -100,10 +100,6 @@ html_to_js("web_components_local") {
 }
 
 js_type_check("extensions_module_resources") {
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/extensions/",
-                    "js_module_root=./gen/chrome/browser/resources/extensions/",
-                  ]
   is_polymer3 = true
   deps = [
     ":checkup",

chrome/browser/resources/extensions/activity_log/BUILD.gn

@@ -16,10 +16,6 @@ html_to_js("web_components") {
 }
 
 js_type_check("closure_compile_module") {
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/extensions/",
-                    "js_module_root=./gen/chrome/browser/resources/extensions/",
-                  ]
   is_polymer3 = true
   deps = [
     ":activity_log",

chrome/browser/resources/welcome/BUILD.gn

@@ -16,10 +16,6 @@ group("closure_compile") {
 
 js_type_check("welcome_files") {
   is_polymer3 = true
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/welcome/",
-                    "js_module_root=./gen/chrome/browser/resources/welcome/",
-                  ]
   deps = [
     ":landing_view",
     ":signin_view",

chrome/browser/resources/welcome/google_apps/BUILD.gn

@@ -6,10 +6,6 @@ import("//third_party/closure_compiler/compile_js.gni")
 import("//tools/polymer/html_to_js.gni")
 
 js_type_check("closure_compile") {
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/welcome/",
-                    "js_module_root=gen/chrome/browser/resources/welcome/",
-                  ]
   is_polymer3 = true
   deps = [
     ":google_app_proxy",

chrome/browser/resources/welcome/ntp_background/BUILD.gn

@@ -6,10 +6,6 @@ import("//third_party/closure_compiler/compile_js.gni")
 import("//tools/polymer/html_to_js.gni")
 js_type_check("closure_compile") {
   is_polymer3 = true
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/welcome/",
-                    "js_module_root=gen/chrome/browser/resources/welcome/",
-                  ]
   deps = [
     ":ntp_background_metrics_proxy",
     ":ntp_background_proxy",

chrome/browser/resources/welcome/set_as_default/BUILD.gn

@@ -7,10 +7,6 @@ import("//tools/polymer/html_to_js.gni")
 
 js_type_check("closure_compile") {
   is_polymer3 = true
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/welcome/",
-                    "js_module_root=gen/chrome/browser/resources/welcome/",
-                  ]
   deps = [ ":nux_set_as_default" ]
 }
 

chrome/browser/resources/welcome/shared/BUILD.gn

@@ -7,10 +7,6 @@ import("//tools/polymer/html_to_js.gni")
 
 js_type_check("closure_compile") {
   is_polymer3 = true
-  closure_flags = default_closure_args + [
-                    "js_module_root=../../chrome/browser/resources/welcome/",
-                    "js_module_root=gen/chrome/browser/resources/welcome/",
-                  ]
   deps = [
     ":bookmark_proxy",
     ":module_metrics_proxy",