Honor 50 millisecond cap for WebKit JavaScript execution.

 Bug 5843118
 WebKit provides a 50 millisecond cap for executing JavaScript
 to ensure that UI remains responsive by allowing recordContent
 in the WebViewCore thread to run.
 JavaSharedClient::ServiceFunctionPtr processes functions until
 they are all complete, circumventing the timeout. This CL
 processes only a single function and then schedules additional
 calls if any remaining calls exist.

Change-Id: I3e013ceeb02da475e0b1e37e715598a2fe048b12

1 files changed, 24 insertions, 23 deletions

diff --git a/Source/WebKit/android/jni/JavaSharedClient.cpp b/Source/WebKit/android/jni/JavaSharedClient.cpp
index 4f40355..4d073c2 100644
--- a/Source/WebKit/android/jni/JavaSharedClient.cpp
+++ b/Source/WebKit/android/jni/JavaSharedClient.cpp
@@ -88,12 +88,12 @@ namespace android {
     FileSystemClient* JavaSharedClient::gFileSystemClient = NULL;
 
     ///////////////////////////////////////////////////////////////////////////
-    
+
     struct FuncPtrRec {
         void (*fProc)(void* payload);
         void* fPayload;
     };
-    
+
     static SkMutex gFuncPtrQMutex;
     static SkDeque gFuncPtrQ(sizeof(FuncPtrRec));
 
@@ -105,33 +105,34 @@ namespace android {
         FuncPtrRec* rec = (FuncPtrRec*)gFuncPtrQ.push_back();
         rec->fProc = proc;
         rec->fPayload = payload;
-        
+
         gFuncPtrQMutex.release();
-        
+
         gTimerClient->signalServiceFuncPtrQueue();
     }
 
     void JavaSharedClient::ServiceFunctionPtrQueue()
     {
-        for (;;) {
-            void (*proc)(void*) = 0;
-            void* payload = 0;
-            const FuncPtrRec* rec;
-
-            // we have to copy the proc/payload (if present). we do this so we
-            // don't call the proc inside the mutex (possible deadlock!)
-            gFuncPtrQMutex.acquire();
-            rec = (const FuncPtrRec*)gFuncPtrQ.front();
-            if (rec) {
-                proc = rec->fProc;
-                payload = rec->fPayload;
-                gFuncPtrQ.pop_front();
-            }
-            gFuncPtrQMutex.release();
-
-            if (!rec)
-                break;
-            proc(payload);
+        // Don't let execution block the WebViewCore thread for too long.
+        void (*proc)(void*) = 0;
+        void* payload = 0;
+        const FuncPtrRec* rec;
+
+        // we have to copy the proc/payload (if present). we do this so we
+        // don't call the proc inside the mutex (possible deadlock!)
+        gFuncPtrQMutex.acquire();
+        rec = (const FuncPtrRec*)gFuncPtrQ.front();
+        if (rec) {
+            proc = rec->fProc;
+            payload = rec->fPayload;
+            gFuncPtrQ.pop_front();
         }
+        bool scheduleAdditionalCall = (gFuncPtrQ.count() > 0);
+        gFuncPtrQMutex.release();
+
+        if (rec)
+            proc(payload);
+        if (scheduleAdditionalCall)
+            gTimerClient->signalServiceFuncPtrQueue();
     }
 }