[chromedriver] Set page load strategy via constructor rather than a setter.

chrome/test/chromedriver/chrome/chrome.h

Index: chrome/test/chromedriver/chrome/chrome.h
diff --git a/chrome/test/chromedriver/chrome/chrome.h b/chrome/test/chromedriver/chrome/chrome.h
index 772be03bf76674cd5a1701d61fb7f486b2a68dab..14251c7c160e08a133dd881027beb79c8fb4d417 100644
--- a/chrome/test/chromedriver/chrome/chrome.h
+++ b/chrome/test/chromedriver/chrome/chrome.h
@@ -50,10 +50,9 @@ class Chrome {
   // actions can be performed on it.
   virtual bool HasTouchScreen() const = 0;
 
+  // Return the page load strategy for this session.
   virtual std::string page_load_strategy() const = 0;
 
-  virtual void set_page_load_strategy(std::string strategy) = 0;
-
   // Quits Chrome.
   virtual Status Quit() = 0;
 };