Move elide_url to its own component

components/secure_display/BUILD.gn

+import("//testing/test.gni")
+
+source_set("secure_display") {
+  sources = [
+    "elide_url.cc",
+    "elide_url.h",
+  ]
+
+  deps = [
+    "//base:base",
+    "//net:net",
+    "//ui/gfx",
+    "//url",
+  ]
+}
+
+source_set("unit_tests") {
+  testonly = true
+  sources = [
+    "elide_url_unittest.cc",
+  ]
+
+  deps = [
+    ":secure_display",
+    "//base:base",
+    "//base/test:test_support",
+    "//testing/gtest",
+  ]
+}