Setting is_component_build to false by default

webrtc/webrtc.gni

Index: webrtc/webrtc.gni
diff --git a/webrtc/webrtc.gni b/webrtc/webrtc.gni
index 96975fae9a4227568632a0fc50932d487cd134ac..877c902735e02e037f5cfa95a68e21c31cd400ab 100644
--- a/webrtc/webrtc.gni
+++ b/webrtc/webrtc.gni
@@ -13,6 +13,21 @@ import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/build.gni")
 import("//testing/test.gni")
+
+if (is_component_build) {
+  print("The Gn argument `is_component_build` is currently " +

[kjellander_webrtc, 2017/03/03 04:19:02]

How about replacing line 17-29 with just:
assert(!is_component_build, 
   """Please avoid using `is_component_build=true`

The GN argument `is_component_build` is currently ignored for WebRTC builds.
Component builds are supported by Chromium and the argument
`is_component_build` makes it possible to create shared libraries instead of
static libraries. If an app depends on WebRTC it makes sense to just depend on
the WebRTC static library, so there is no difference between
`is_component_build=true` and `is_component_build=false`

More info about component builds at: 
https://chromium.googlesource.com/chromium/src/+/master/docs/component_build.md
""")

[mbonadei, 2017/03/03 18:03:59]

Yeah, this would be cleaner than the current solution but it seems that newlines
are not supported in a string constant:
ERROR at //webrtc/webrtc.gni:18:10: Newline in string constant.
       """Please avoid using `is_component_build=true`.
         ^---------------------------------------------

And adding '\n' does not create a newline.

[kjellander_webrtc, 2017/03/03 19:10:03]

I see, then this is fine.

+        "ignored for WebRTC builds.")
+  print("Component builds are supported by Chromium and the argument " +
+        "`is_component_build` makes it possible to create shared libraries " +
+        "instead of static libraries.")
+  print("If an app depends on WebRTC it makes sense to just depend on the " +
+        "WebRTC static library, so there is no difference between " +
+        "`is_component_build=true` and `is_component_build=false`.")
+  print(
+      "More info about component builds at: " + "https://chromium.googlesource.com/chromium/src/+/master/docs/component_build.md")
+  assert(!is_component_build, "Please avoid using `is_component_build=true`.")

[kjellander_webrtc, 2017/03/03 19:10:03]

I suggest changing to "Please avoid using `Component builds are not supported in
WebRTC."

+}
+
 if (is_ios) {
   import("//build/config/ios/rules.gni")
 }