Expose way to set google api key through CWVWebView class method.

ios/web_view/internal/cwv_web_view.mm

Index: ios/web_view/internal/cwv_web_view.mm
diff --git a/ios/web_view/internal/cwv_web_view.mm b/ios/web_view/internal/cwv_web_view.mm
index 08fb4d8dc30b2994005f51fbd5799b2b1efbc42c..a464f749856ea5d9ecd75921b8d63bdda3118d5e 100644
--- a/ios/web_view/internal/cwv_web_view.mm
+++ b/ios/web_view/internal/cwv_web_view.mm
@@ -10,6 +10,7 @@
 #import "base/ios/weak_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/sys_string_conversions.h"
+#include "google_apis/google_api_keys.h"
 #import "ios/web/public/navigation_manager.h"
 #include "ios/web/public/referrer.h"
 #include "ios/web/public/reload_type.h"
@@ -60,6 +61,21 @@
 @synthesize estimatedProgress = _estimatedProgress;
 @synthesize UIDelegate = _UIDelegate;
 
++ (void)setGoogleAPIKey:(NSString*)googleAPIKey
+               clientID:(NSString*)clientID
+           clientSecret:(NSString*)clientSecret {
+  google_apis::SetAPIKey(base::SysNSStringToUTF8(googleAPIKey));
+
+  std::string client_id = base::SysNSStringToUTF8(clientID);

[Eugene But (OOO till 7-30), 2017/04/13 15:06:25]

client_id Style is used for C++ code, Objective-C code should follow clientID
Style

[jzw1, 2017/04/14 02:10:32]

Any suggestions for what I should call it since clientID is already used by the
method parameter? Going with clientIDString for now.

[Eugene But (OOO till 7-30), 2017/04/14 14:24:48]

Maybe clientIDNSString? But clientIDString looks fine.

+  std::string client_secret = base::SysNSStringToUTF8(clientSecret);
+  for (size_t i = 0; i < google_apis::CLIENT_NUM_ITEMS; ++i) {
+    google_apis::OAuth2Client client =
+        static_cast<google_apis::OAuth2Client>(i);
+    google_apis::SetClientID(client_id, client);
+    google_apis::SetClientSecret(client_secret, client);
+  }

[Roger Tawa OOO till Jul 10th, 2017/04/13 17:42:43]

Does this need to loop?  In what cases will the ios webview need any client
other than CLIENT_MAIN?

[michaeldo, 2017/04/13 19:28:09]

I also think this loop is odd here. (If we do need it, can it be moved to
google_api_keys.cc and remove the client param all together?)

[jzw1, 2017/04/14 02:10:32]

Currently there's a piece of translate code:
https://cs.chromium.org/chromium/src/components/translate/core/browser/transl...
that checks if all the client ids and client secrets are defined. if any of them
isn't, it won't proceed.

+}
+
 - (instancetype)initWithFrame:(CGRect)frame
                 configuration:(CWVWebViewConfiguration*)configuration {
   self = [super initWithFrame:frame];