Pass False for fromSurface argument to Page.captureScreenshot.

telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py

Index: telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py
diff --git a/telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py b/telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py
index 0c37347fc88986c731aad32efb9812dc17fb2e3e..3ca06345d8a363309eced59ad65d880e92303474 100644
--- a/telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py
+++ b/telemetry/telemetry/internal/backends/chrome_inspector/inspector_page.py
@@ -138,7 +138,12 @@ class InspectorPage(object):
 
   def CaptureScreenshot(self, timeout=60):
     request = {
-        'method': 'Page.captureScreenshot'
+        'method': 'Page.captureScreenshot',
+        # TODO(rmistry): when Chrome is running in headless mode, this
+        # will need to pass True. Telemetry needs to understand
+        # whether the browser is in headless mode, and pass that
+        # knowledge down to this method.
+        'fromSurface': False
         }
     # "Google API are missing..." infobar might cause a viewport resize
     # which invalidates screenshot request. See crbug.com/459820.